2011

Bioasphalt is a binder for road surfacing made from renewable, non petroleum feedstocks such as vegetable oils, sugar and molasses, starches, lignin, pine resin and waste cooking oil, in place of the bitumen left over from refining crude oil.

• Statement 1 is correct, since the defining feature of bioasphalt is that it is not derived from fossil fuels.
• Statement 2 is incorrect: the point of the material is that it is made from renewable resources, and a binder from non renewable resources would simply be conventional asphalt.
• Statement 3 is correct, because organic wastes, including agricultural residues and used oils, are among the feedstocks being developed.
• Statement 4 is correct: replacing a petroleum product with a renewable one lowers the fossil carbon locked into road building, and some bio binders can be laid at lower temperatures, reducing emissions during paving.
• Statements 1, 3 and 4 being correct, the official answer is (b). Elimination route: statements 1 and 2 contradict each other, so (a) and (d), which contain both, fall, and (c) falls with statement 2.

Coal is mostly carbon, with hydrogen, a little sulphur, some nitrogen and a mineral fraction that leaves as ash, and each element yields its own pollutant when it burns in a power plant boiler.

• Statement 1 is correct: the oxidation of carbon gives carbon dioxide, and coal fired generation is the largest single source of India's carbon dioxide emissions.
• Statement 2 is correct: oxides of nitrogen form both from nitrogen bound in the fuel and from the reaction of atmospheric nitrogen and oxygen at furnace temperatures, which is why almost any combustion produces them.
• Statement 3 is correct: the sulphur in coal, as pyrite and in organic compounds, burns to sulphur dioxide; Indian coal is relatively low in sulphur, yet the sheer volume burnt makes power plants a major source. All three being emissions, the official answer is (d). Since this paper, the 2015 emission standards for thermal plants have required flue gas desulphurisation. Elimination route: knowing that high temperature combustion in air forms nitrogen oxides, a candidate need only recall that coal contains carbon and sulphur.

A geostationary orbit is the special case of a geosynchronous orbit in which the satellite appears fixed above one point of the equator, so a ground antenna can point at it permanently, which is why INSAT and GSAT telecommunication satellites are placed there.

• Statement 1 is correct: the orbit must be geosynchronous, with a period of one sidereal day, about 23 hours 56 minutes, matching the Earth's rotation.
• Statement 2 is correct: the orbit must be circular, since an elliptical orbit would make the satellite speed up and slow down and so drift east and west of its station.
• Statement 3 is correct: the orbit must lie in the equatorial plane, since an inclined geosynchronous orbit traces a figure of eight in the sky.
• Statement 4 is incorrect as written: the altitude is about 35,786 kilometres, which is about 22,236 miles; the statement presents the mileage in kilometres.
• Statements 1, 2 and 3 being correct, the official answer is (a). Elimination route: a candidate who remembers the altitude as roughly 36,000 kilometres eliminates (b), (c) and (d) at once.

Food inflation in India stayed in double digits through much of 2009-10 and 2010-11, and the Economic Survey and the Reserve Bank explained it chiefly through the composition of demand and the structure of supply.

• Statement 1 is incorrect: the area under food grains did not fall by anything like 30 percent in five years; it hovered around 120 to 125 million hectares, and 2010-11 brought a record harvest.
• Statement 2 is correct: rising incomes shifted consumption towards milk, eggs, meat, fish, fruit and vegetables, and it was precisely these protein rich and perishable items whose prices rose fastest.
• Statement 3 is correct: the food supply chain suffers from structural constraints, including inadequate cold storage, warehousing and transport, intermediaries under the state APMC Acts and post harvest losses, so supply cannot respond quickly to the new pattern of demand.
• Statements 2 and 3 being correct, the official answer is (b). Elimination route: the extreme and precise figure in statement 1 is the giveaway, and once it is rejected only (b) remains.

Gene mapping establishes the order of genes and DNA markers along a chromosome and the distances between them, linking a stretch of DNA with a trait.

• Statement 1 is correct: DNA markers such as microsatellites are inherited predictably, so they can verify parentage and establish the pedigree of livestock, which matters for breed registration and breeding programmes.
• Statement 2 is incorrect because of the word all: many diseases are infectious, nutritional or environmental in origin, and even among those with a genetic component most are polygenic and shaped by the environment, so a gene map cannot by itself reveal the causes of all human diseases.
• Statement 3 is correct: once the genes or markers linked with disease resistance are located, breeders can use marker assisted selection to identify and propagate animals that carry them, developing disease resistant breeds faster than by conventional selection.
• Statements 1 and 3 being correct, the official answer is (c). Elimination route: the absolute word in statement 2 removes (a), (b) and (d), a pattern the Commission uses often in science questions.

In balance of payments accounting, a transaction is classified by the residence of the parties, not by where it takes place. When a non resident spends money in India on hotels, transport, food, tickets and shopping, an Indian resident is selling a service to a foreigner and receiving foreign exchange. Such spending is recorded as an export of services, under travel in the invisibles of the current account.

• Option (a) is correct for this reason.
• Option (b) is wrong: import describes the opposite case, an Indian resident spending abroad.
• Option (c) is wrong because production is the creation of goods and services within the economy, whoever buys them, and says nothing about this transaction in the external accounts.
• Option (d) is wrong in the national accounts sense: the visitors are consuming, but their spending is not part of domestic private final consumption expenditure, which covers residents; it enters gross domestic product through net exports. The official answer is (a). Elimination route: tourism earnings are a standard invisible export, and a candidate who sees the Games as a foreign exchange earner reaches (a) directly.

A microbial fuel cell converts the chemical energy of organic matter directly into electricity using bacteria as the catalyst: bacteria such as Geobacter and Shewanella oxidise an organic substrate at the anode, and the electrons flow through an external circuit to the cathode, where they combine with protons and oxygen to form water.

• Statement 1 is correct, since living organisms as catalysts are the defining feature of the device, letting it run at ordinary temperatures without precious metal catalysts at the anode.
• Statement 2 is incorrect: the substrates are organic, such as acetate, glucose, starch and the organic load in sewage or effluent, because the microbes derive their energy by oxidising organic carbon.
• Statement 3 is correct: the organic matter in waste water is exactly the fuel the bacteria need, so the cell can lower the effluent's biochemical oxygen demand while generating a small current, its principal application.
• Statements 1 and 3 being correct, the official answer is (c). Elimination route: knowing that microbes break down organic matter rejects statement 2, leaving (a) or (c), and the waste water application settles it.

A fiscal stimulus is a deliberate increase in government spending, a cut in taxes, or both, to raise aggregate demand when the economy is slowing, accepting a wider fiscal deficit for a time. India used one after the global financial crisis of 2008, with three packages between December 2008 and February 2009, and the rollback began with the partial restoration of excise duties in the Budget for 2010-11.

• Option (b) is correct because it describes the measure in its general sense, an active government effort to boost economic activity.
• Option (a) is wrong because a stimulus is applied when demand is weak, not to meet a surge from rapid growth, which would call for restraint, and it is not confined to manufacturing.
• Option (c) is wrong because directing lending to agriculture is credit policy, and containing food inflation runs counter to a stimulus's expansionary intent.
• Option (d) is wrong because financial inclusion is a distinct, long term objective concerned with access to banking. The official answer is (b). Elimination route: stimulus means a push to the whole economy, and only (b) has that breadth.

The Antarctic ozone hole forms each southern spring through chemistry and polar meteorology together. In winter a strong, stable polar vortex, bounded by the polar front jet, isolates the air over Antarctica and lets it cool below about minus 78 degrees Celsius, when polar stratospheric clouds form. On their particles, the chlorine reservoirs hydrogen chloride and chlorine nitrate are converted into molecular chlorine, which comes overwhelmingly from chlorofluorocarbons released at the surface. When sunlight returns in September, the chlorine is split into free radicals that destroy ozone catalytically.

• Option (b) is correct because it names both the meteorological condition and the chemical input.
• Option (a) is wrong because the process takes place in the stratosphere, not through tropospheric turbulence.
• Option (c) is wrong on both counts: it is the presence, not the absence, of the polar front and stratospheric clouds that matters, and methane is not an ozone depleting substance in this sense.
• Option (d) is wrong because global warming does not cause the hole. The official answer is (b). Elimination route: (b) and (c) are mirror images, and knowing that polar stratospheric clouds help destroy ozone settles it.

The current account records trade in goods and services, primary income and transfers, and its deficit measures how far a country spends abroad on these beyond what it earns.

• Statement 1 is correct in the standard analysis: devaluation makes exports cheaper abroad and imports dearer at home, and provided demand is sufficiently price elastic, the current account improves after a lag.
• Statement 2 is incorrect: reducing an export subsidy raises the price at which exporters sell abroad, reduces exports and widens the deficit.
• Statement 3 is accepted in the key. Strictly, foreign direct investment and foreign institutional investment are recorded in the capital and financial account and finance a current account deficit rather than reduce it; the key reads the statement broadly, since direct investment builds export capacity and brings technology and market access, narrowing the deficit over time. The official answer is (d). Elimination route: statement 2 is the clear wrong item, which removes (a) and (b), and since no option offers statement 1 alone, a candidate who accepts devaluation is led to (d).

The Constitution (Seventy third Amendment) Act, 1992 added Part IX, Articles 243 to 243O, and the Eleventh Schedule, giving panchayats constitutional status.

• Statement 2 is correct: Article 243K vests the superintendence, direction and control of electoral rolls and all panchayat elections in a State Election Commission.
• Statement 3 is correct: Article 243I requires the Governor to constitute a Finance Commission within one year of the Amendment's commencement and every five years thereafter to review panchayat finances.
• Statement 1 is accepted in the key. The District Planning Committee itself is in Article 243ZD, inserted by the Seventy fourth Amendment for municipalities; but the two Amendments were framed together as one design for planning from below, with Article 243G requiring panchayats to prepare plans for economic development and social justice, and the Committee consolidates the plans of panchayats and municipalities into a draft district plan. On that reading it is part of the Seventy third Amendment's scheme. The official answer is (d). The item is decided entirely by how widely a candidate reads statement 1.

Bhitarkanika in Kendrapara district of Odisha lies in the delta formed where the Brahmani and the Baitarani meet before entering the Bay of Bengal at the Dhamra mouth. The Brahmani is formed by the South Koel and the Sankh, both rising on the Chota Nagpur plateau, which meet at Vedavyas near Rourkela; the Baitarani rises in the Gonasika hills of Keonjhar. Bhitarkanika is a national park with one of the largest mangrove forests on the east coast after the Sundarbans and India's largest population of the estuarine crocodile, Crocodylus porosus, and a Ramsar site since 2002.

• Option (a) is correct.
• Option (b) is wrong because Chandipur on sea, in Balasore, is a beach known for its receding tide and as a missile test range.
• Option (c) is wrong because Gopalpur on sea, in Ganjam, is a beach and port town in the south of the state.
• Option (d) is wrong because Simlipal is an inland tiger reserve on the Mayurbhanj plateau, far from the coast. The official answer is (a). Elimination route: only Bhitarkanika is both coastal and deltaic among the four.

The annual inflation rate is the percentage change in a price index over the same month of the previous year, so any month's reading depends as much on prices a year earlier as on prices today. That dependence is the base effect: if prices were unusually low a year ago, even a modest current level shows a high rate; if unusually high, the rate looks subdued even while prices rise.

• Option (c) is correct because it states exactly this: the impact of the previous year's price levels on the calculation of the inflation rate.
• Option (a) is wrong because a crop failure is a supply shock, a real cause of rising prices rather than an arithmetical effect of the base.
• Option (b) is wrong because a demand surge from rapid growth is demand pull inflation, again a real cause.
• Option (d) falls because (c) is correct. The official answer is (c). Elimination route: the word base points to the denominator, and only (c) refers to the calculation at all.

A demographic dividend is the boost to growth possible when the share of the working age population, conventionally those aged 15 to 64, rises relative to the dependent young and old. It arises during the demographic transition: as fertility falls, the large cohorts born earlier move into working age and the dependency ratio declines, so a larger share of the population can work, save and invest. India's working age share was rising at the date of this paper.

• Option (b) is correct for this reason.
• Option (a) is wrong because a large population below 15 years raises the dependency ratio; it becomes a dividend only when those children reach working age.
• Option (c) is wrong because a large elderly population is the opposite condition, an ageing burden of the kind Japan and much of Europe face.
• Option (d) is wrong because total population size says nothing about age structure; a large population with a high dependency ratio yields no dividend. The official answer is (b). Elimination route: dividend implies productive workers, and only the working age band in (b) supplies them.

A carbon credit is a tradable permit representing one tonne of carbon dioxide or its equivalent in other greenhouse gases. The system was created under the Kyoto Protocol of 1997, which set binding targets for the industrialised Annex I countries and let them meet part of them through emissions trading, joint implementation and the Clean Development Mechanism.

• Statement (a) is correct, since the credit system was established in conjunction with the Protocol.
• Statement (b) is correct: credits accrue to those that cut emissions below their quota and can be sold to those that exceed theirs.
• Statement (c) is correct: the scheme exists to limit the growth of emissions at least cost.
• Statement (d) is the incorrect one and so the answer: carbon credits are traded at prices set by supply and demand, on exchanges such as the European Climate Exchange, not at a price fixed by the United Nations Environment Programme, which has no price setting role. The official answer is (d). Elimination route: a tradable credit implies a market price, which makes (d) the odd statement out.

Value Added Tax is a tax on the value added at each stage of production and distribution, collected in stages through input tax credit.

• Statement (a) is a feature: VAT is levied at many points along the chain, and as implemented in India it was destination based, accruing on consumption within the state.
• Statement (b) is a feature, since taxing value addition at each stage is the definition of the tax.
• Statement (c) is a feature: because each dealer recovers the tax paid on inputs, the burden passes forward to the final consumer, making VAT in substance a consumption tax.
• Statement (d) is not a feature and is the answer: sales tax was a state subject under Entry 54 of the State List, and VAT was introduced by the States themselves from April 2005, replacing their sales taxes, the Union playing only a facilitating role. The official answer is (d). Since then the Goods and Services Tax, introduced in July 2017, has subsumed state VAT on most goods. Elimination route: knowing that VAT was a State tax is enough to pick out (d).

An economy is open or closed according to whether it has transactions with the rest of the world. A closed economy has no foreign trade at all, neither exporting nor importing, and in strict usage no flows of capital or factor income across its borders, so national income equals domestic expenditure with no net exports term. It is chiefly a theoretical construct, since every actual economy trades to some extent.

• Option (d) is correct because it gives exactly this definition.
• Option (a) is wrong because control of the money supply is monetary policy, exercised by the central bank in open and closed economies alike.
• Option (b) is wrong because deficit financing, borrowing or creating money to cover a budget deficit, is a fiscal practice found in every kind of economy.
• Option (c) is wrong because an economy that exports is by definition engaged in foreign trade and so is open, and it cannot sustain exports without ever importing. The official answer is (d). Elimination route: closed refers to the borders of the economy, and only (d) speaks of trade across them.

Girdling, removing a complete ring of bark around the trunk, strips away the phloem, which lies just inside the bark, while leaving the xylem, the wood, intact. The xylem carries water and minerals upward to the leaves and, lying deeper, keeps functioning. The phloem carries sugars made in the leaves downward to the rest of the plant, including the roots; once it is cut, the roots receive no food, exhaust their reserves, stop growing and absorbing, and eventually die, after which the whole tree dries up.

• Option (b) is correct for this reason.
• Option (a) is wrong because water rises through the xylem, which girdling does not remove, which is also why the tree declines gradually rather than dying at once.
• Option (c) is wrong because infection by soil microbes may follow but is not the cause of death.
• Option (d) is wrong because roots obtain oxygen from the air spaces in the soil, not through the bark. The official answer is (b). Elimination route: the phrase gradually dries up rules out the immediate failure of water supply implied by (a).

New START, the Treaty on Measures for the Further Reduction and Limitation of Strategic Offensive Arms, was signed by the United States and Russia in Prague on 8 April 2010 and entered into force on 5 February 2011, replacing START I of 1991, which had expired in December 2009. It limited each side to 1,550 deployed strategic warheads and 700 deployed intercontinental ballistic missiles, submarine launched ballistic missiles and heavy bombers, for ten years.

• Option (a) is correct because the treaty is bilateral, concerns strategic nuclear arms and is between the United States and Russia.
• Option (b) is wrong because the East Asia Summit has no energy security treaty of this name.
• Option (c) is wrong because the European Union is not a party to strategic arms control.
• Option (d) is wrong because BRICS had no such multilateral trade treaty. The official answer is (a). Since then the treaty was extended in 2021 for five years to February 2026, and Russia suspended its participation in 2023. Elimination route: START stands for Strategic Arms Reduction Treaty, which points straight to (a).

Only about half of the carbon dioxide released by fossil fuel burning and land use change stays in the atmosphere; the rest is taken up by land and ocean sinks.

• Statement 1 is incorrect: carbon dioxide is a long lived, well mixed gas that does not escape to the outer stratosphere or to space in any significant amount; it is heavier than air and remains distributed through the atmosphere, which is why it accumulates.
• Statement 2 is correct: photosynthesis by phytoplankton, roughly half of global primary production, is a major route by which carbon dioxide is removed from the air, part of it sinking to the deep sea as dead organic matter.
• Statement 3 is incorrect: polar ice traps small bubbles of air as snow is compacted, which is why ice cores preserve past atmospheres, but the volume is minute and no sink of consequence for modern emissions. Only statement 2 being correct, the official answer is (b). Elimination route: statement 1 contradicts the very reason carbon dioxide causes concern, its persistence, and statement 3 confuses a record with a sink.

Upwelling is the rise of cold, deep water to the surface, usually where winds blow parallel to a coast and drive surface water offshore, as off Peru and California, and seasonally along the south west coast of India in the monsoon. The deep water is rich in nitrates, phosphates and silicates, because sinking organic matter decomposes at depth, while phytoplankton strip sunlit surface waters of them.

• Statement 2 is correct: by returning these nutrients to the sunlit zone, upwelling fuels intense phytoplankton growth, supporting zooplankton and fish, so upwelling zones, a fraction of one percent of the ocean's area, yield a large share of the world's fish catch.
• Statement 1 is incorrect because decomposers are found throughout the water column and sediments, and it is their products, the nutrients, not the organisms, that upwelling transports.
• Statement 3 is incorrect because benthic organisms live on and in the sea floor and are not lifted by upwelling; nor would that raise productivity, which depends on primary producers. Only statement 2 being correct, the official answer is (b). Elimination route: productivity needs light and nutrients, and only statement 2 supplies the missing nutrient.

A tropical rain forest looks luxuriant, but most of its nutrients are held in the living biomass rather than the soil. High temperature and constant moisture make decomposition very rapid, the nutrients released are taken up at once by a dense surface mat of roots and fungal partners, and heavy rainfall leaches the rest, leaving poor, often lateritic soils. When the forest is cleared, the nutrient store goes with the trees, the exposed soil is quickly leached and eroded, and regeneration is slow. A tropical deciduous forest, with a dry season and thicker litter and humus, retains more nutrients and recovers faster.

• Option (a) is correct for this reason.
• Option (b) is wrong because the seeds of many rain forest trees, though short lived, are not of poor viability as a rule; the limiting factor is the site.
• Option (c) is wrong because many rain forest species, especially pioneers, grow very fast.
• Option (d) is wrong on its premise, since the soil is not fertile. The official answer is (a). Elimination route: (d) assumes fertile soil and (a) denies it, and knowing the nutrient poverty of laterite resolves the pair.

The Himalaya lies where several biogeographic realms meet. Its fauna and flora combine Palaearctic elements from the north, such as the snow leopard, Indo Malayan elements from the south and east, such as hornbills and many primates, and many endemic species that evolved in its isolated valleys, while its great range in altitude further multiplies habitats.

• Option (b) is correct because the convergence of biogeographic zones is the most appropriate single explanation for this richness, and the reason the eastern Himalaya is part of a recognised hotspot.
• Option (a) is wrong as the most appropriate reason: rainfall is high only in the east and south, while the dry trans Himalaya is still distinctive in species, and rainfall explains luxuriance of growth rather than diversity of species.
• Option (c) is wrong as a matter of fact, since invasives such as Lantana camara and Ageratina adenophora are widespread there, and their absence would preserve diversity, not create it.
• Option (d) is wrong because human pressure in the Himalaya is considerable, and low interference again only protects existing richness. The official answer is (b).

Biodiversity conservation in India rests not only on the Wildlife (Protection) Act, 1972 and the Biological Diversity Act, 2002 but on laws whose primary subject lies elsewhere.

• Statement 1 is relevant: the Imports and Exports (Control) Act, 1947, until the Foreign Trade (Development and Regulation) Act, 1992 replaced it, was the instrument through which trade in wild animals, plants and their products was prohibited or restricted.
• Statement 2 is relevant: the Mines and Minerals (Development and Regulation) Act, 1957, named loosely in the question, governs mining leases, and its rules provide for protecting the environment and restoring mined land, mining being a main threat to forests and habitat.
• Statement 3 is relevant: the Customs Act, 1962 empowers officers to seize goods whose import or export is prohibited, the principal means of intercepting smuggled wildlife products such as ivory and tiger parts.
• Statement 4 is relevant: the Indian Forest Act, 1927 provides for reserved, protected and village forests and regulates the felling and transit of timber. All four Acts bearing on conservation, the official answer is (c). The item is hard because only the Forest Act is obviously environmental.

Karl Marx explained history as a succession of struggles between classes defined by their relation to the means of production, slave and master, serf and lord, worker and capitalist, grounded in a materialist reading of Hegel's dialectic. For Hegel, history moved through the conflict of ideas, thesis, antithesis and synthesis; Marx turned Hegel right side up, so that material conditions, the forces and relations of production, develop through contradiction, and ideas, law and politics follow from them. This method, applied to society as historical materialism, was later systematised as dialectical materialism, and option (d) is correct.

• Option (a) is wrong because empirical liberalism, the tradition of Locke and Mill, centres on individual rights and limited government, not a struggle of classes.
• Option (b) is wrong because existentialism, the philosophy of Kierkegaard, Heidegger and Sartre, concerns individual freedom and choice and has no theory of class.
• Option (c) is wrong because Darwin's theory explains biological evolution through natural selection; Marx admired it but did not derive class struggle from it. The official answer is (d).

The ionosphere, from about 60 to over 400 kilometres up, consists of layers in which solar ultraviolet and X ray radiation ionises atmospheric gases, producing free electrons and ions. High frequency radio waves, roughly 3 to 30 megahertz, are refracted by these layers strongly enough to bend back to the ground, and this sky wave propagation lets short wave signals travel beyond the horizon.

• Statement 1 is incorrect: ozone is concentrated in the stratosphere, between about 15 and 35 kilometres, well below the ionosphere, and absorbs ultraviolet radiation; it plays no part in reflecting radio waves.
• Statement 2 is incorrect as a reason: radio waves do have long wavelengths compared with light, but that is not why the ionosphere facilitates communication, and shorter wavelength bands such as very high frequency and microwave pass through it instead of returning, which is why satellites are used for television and telephony. Neither statement explaining the phenomenon, the official answer is (d). The item is hard because statement 2 sounds true; it is ionisation, which neither statement mentions, that does the work.

Foreign direct investment gives the investor a lasting interest and significant influence in an enterprise, conventionally 10 percent or more of its equity, through new plants, joint ventures and acquisitions. Foreign institutional investment is portfolio investment by pension funds, mutual funds and insurance companies registered with SEBI, buying traded shares and bonds without seeking control.

• Option (b) is correct in the sense the Commission intends: portfolio money adds to the general pool of capital by flowing into the stock and bond markets at large, while direct investment is committed to particular enterprises and sectors.
• Option (a) is wrong because it reverses the roles: it is FDI that brings management skills, technology and market access with capital, while FII brings only capital.
• Option (c) is wrong because FII flows mainly into the secondary market, buying listed securities, whereas FDI goes into the enterprise itself.
• Option (d) is wrong because FII is hot money, far more volatile than FDI. The official answer is (b). Since then the FII category has been merged into the Foreign Portfolio Investor regime under the SEBI regulations of 2014.

Bt brinjal carries the cry1Ac gene from the soil bacterium Bacillus thuringiensis, which makes the plant produce a crystal protein toxic to particular insect larvae. Its target is the fruit and shoot borer, Leucinodes orbonalis, the most destructive pest of brinjal in India; the protein binds to receptors in the larva's gut and kills it.

• Option (a) is correct because the objective of the modification is resistance to this pest.
• Option (b) is wrong because the Bt gene does nothing for taste or nutrition.
• Option (c) is wrong because drought tolerance requires quite different genes.
• Option (d) is wrong because a longer shelf life is the aim of other modifications, as in the Flavr Savr tomato. The official answer is (a). Bt brinjal, developed by Mahyco, was approved by the Genetic Engineering Approval Committee in October 2009, but the Environment Minister placed a moratorium on its release in February 2010, which remains in force in India; Bangladesh has since approved it. Elimination route: knowing that Bt cotton was made to resist the bollworm is enough.

Aam Admi Bima Yojana was launched on 2 October 2007 as a social security scheme for rural landless households, administered by the Life Insurance Corporation of India.

• Statement 1 is correct: the insured had to be the head of the family or one earning member of a rural landless household.
• Statement 2 is incorrect: the eligible age band was 18 to 59 years, not 30 to 65.
• Statement 3 is correct: under the add on Shiksha Sahyog Yojana, a scholarship of 100 rupees a month, paid half yearly, was available for up to two children of the insured in classes 9 to 12, including industrial training institutes, without extra premium.
• Statements 1 and 3 being correct, the official answer is (c). Since then, Aam Admi Bima Yojana has been converged with the Pradhan Mantri Jeevan Jyoti Bima Yojana and the Pradhan Mantri Suraksha Bima Yojana. Elimination route: a candidate who knows the scheme covered working age adults can reject the upper limit of 65 in statement 2, leaving (a) or (c), and the scholarship is the scheme's best known feature.

Brent is one of the major benchmark grades against which most of the world's crude oil is priced, the others being West Texas Intermediate and Dubai and Oman.

• Statement 1 is correct: Brent is a classification of crude oil in the sense of a benchmark grade, and about two thirds of internationally traded oil is priced off it.
• Statement 2 is correct: the name comes from the Brent oilfield in the North Sea, between Scotland and Norway, and the benchmark today is a blend of several North Sea streams.
• Statement 3 is incorrect: Brent is a light sweet crude, sweet meaning low in sulphur, about 0.37 percent, but low is not none, and practically all crude contains some sulphur, which refineries must remove.
• Statements 1 and 2 being correct, the official answer is (b). Elimination route: the absolute claim in statement 3 is the planted error, since sulphur free crude does not occur in nature, which removes (c) and (d), and the widely known North Sea origin removes (a).

In a thermal nuclear reactor, uranium 235 nuclei split when struck by neutrons, but fission neutrons are fast, carrying about two million electron volts, and fast neutrons are much less likely than slow, thermal ones to cause further fission. A moderator slows them by repeated collisions with light nuclei. Heavy water, deuterium oxide, is an excellent moderator because deuterium is light enough to absorb much of a neutron's energy at each collision yet, unlike ordinary hydrogen, absorbs very few neutrons itself, which is why heavy water reactors can run on natural, unenriched uranium; they are the core of the first stage of India's nuclear programme.

• Option (a) is correct for this reason.
• Option (b) is wrong because a moderator does the opposite of speeding neutrons up.
• Option (c) is partly true of Indian pressurised heavy water reactors, in which heavy water also circulates as the primary coolant, but cooling is not its distinctive function.
• Option (d) is wrong because stopping the reaction is the job of control rods of boron or cadmium. The official answer is (a). Elimination route: moderator is the standard textbook answer.

The Constitution does not use the term national minority. Religious minorities at the national level are those notified under the National Commission for Minorities Act, 1992; at the date of this paper these were Muslims, Christians, Sikhs, Buddhists and Parsis, and Jains were added in 2014.

• Statement 1 is correct: Article 30 gives all minorities, religious or linguistic, the right to establish and administer educational institutions of their choice, without discrimination in grants of aid.
• Statement 2 is incorrect: there is no provision for the President to nominate a representative of any religious community to the Lok Sabha; the only such nomination then was under Article 331, for up to two Anglo Indians, who are not a religious minority, and even that was discretionary.
• Statement 3 is correct: the Prime Minister's New 15 Point Programme of 2006 covers the notified minorities.
• Statements 1 and 3 being correct, the official answer is (c). Since then the nomination of Anglo Indians to the Lok Sabha has ended, the One Hundred and Fourth Amendment not extending it beyond January 2020. Elimination route: the word automatically in statement 2 marks it as false.

At the date of this paper the governing law was the Persons with Disabilities (Equal Opportunities, Protection of Rights and Full Participation) Act, 1995.

• Statement 1 is correct: Section 26 required governments and local authorities to ensure every child with a disability had access to free education in an appropriate environment until eighteen, longer than the age limit of fourteen under the Right of Children to Free and Compulsory Education Act, 2009.
• Statement 2 is correct: Section 43 required governments to frame schemes for the preferential allotment of land at concessional rates for housing, business and other purposes.
• Statement 3 is correct: Section 46 required governments, within their economic capacity, to provide ramps in public buildings, along with adapted toilets for wheelchair users and Braille signals in lifts. All three being benefits under the law, the official answer is (d). Since then the 1995 Act has been replaced by the Rights of Persons with Disabilities Act, 2016, which keeps free education for children with benchmark disabilities from six to eighteen years. The item is hard only because the Act's sections are rarely read.

The Mega Food Park Scheme of the Ministry of Food Processing Industries, approved in 2008, sought to build modern food processing infrastructure from farm to market on a hub and spoke model: collection and primary processing centres near farms linked to a central processing centre with common facilities such as cold storage, warehousing, testing laboratories and packaging.

• Statement 1 is correct: good infrastructure for the industry, especially common facilities small units could not afford alone, is the core purpose.
• Statement 2 is correct: by linking farmers directly with processors and providing cold chains near production, the scheme aimed to increase the processing of perishables such as fruit, vegetables, milk and fish and to reduce the large wastage between farm and consumer.
• Statement 3 is not among the stated objectives: the parks provide infrastructure and land on which entrepreneurs set up their own units with technology of their choosing; the scheme does not itself supply processing technologies, eco friendly or otherwise.
• Statements 1 and 2 being correct, the official answer is (b). The item is hard because statement 3 sounds like a natural aim of any modern food park.

Article 266 establishes the Consolidated Fund of India, into which go all Union revenues, the loans it raises and loan repayments it receives, and clause (3) provides that no money shall be appropriated out of it except in accordance with law and in the manner the Constitution provides. Article 114 gives the procedure: after the Lok Sabha votes the demands for grants, an Appropriation Bill provides for withdrawing the money needed for the grants and the charged expenditure, and no money can be withdrawn except under such a law. Parliamentary control of the purse is the principle at work, and option (b) is correct.

• Option (a) is wrong because the President's role is formal, demands for grants being made on the President's recommendation, but the authority to withdraw comes from the Act of Parliament.
• Option (c) is wrong because the Prime Minister leads the Government that proposes expenditure but cannot authorise withdrawals.
• Option (d) is wrong because the Finance Minister presents the Budget and manages expenditure but cannot withdraw money without the authority of Parliament. The official answer is (b). Elimination route: no expenditure without parliamentary sanction is the governing rule, and only (b) names Parliament.

The Constitution provides three funds of the Government of India. Under Article 266(1), all Union revenues, the loans it raises and loan repayments it receives form the Consolidated Fund of India. Under Article 266(2), all other public money, such as provident fund deposits and small savings, is credited to the Public Account of India, where the Government acts more as a banker. Under Article 267, the Contingency Fund of India is placed at the President's disposal for unforeseen expenditure pending authorisation by Parliament.

• Option (c) is correct because tax revenue and other receipts for the conduct of Government business are precisely the revenues that go into the Consolidated Fund.
• Option (a) is wrong because the Contingency Fund is a fixed imprest amount drawn from and recouped to the Consolidated Fund, not the account into which revenues flow.
• Option (b) is wrong because the Public Account holds money that does not belong to the Government outright.
• Option (d) is wrong because deposits and advances are a section within the Public Account, not a separate fund. The official answer is (c). Elimination route: all revenues points straight to the Consolidated Fund.

Microfinance is the provision of a broad range of financial services to poor and low income households who lack access to formal banking.

• Statement 1 is correct: credit, usually small collateral free loans through joint liability or self help groups, is the best known service, India's two main channels being NABARD's bank linked self help group programme and microfinance institutions.
• Statement 2 is correct: savings are central, self help group members pooling regular savings before they borrow, though microfinance companies registered as NBFCs cannot accept public deposits.
• Statement 3 is correct: microinsurance, covering life, health, crops and livestock at small premiums, is a recognised component, and the IRDA issued Micro Insurance Regulations in 2005.
• Statement 4 is correct: fund transfer and remittance services, increasingly through business correspondents and mobile platforms, are part of the range, enabling migrant workers to send money home. All four being microfinance services, the official answer is (d). Elimination route: microfinance is deliberately wider than microcredit, and the stem speaks of financial services in the plural, which points to the all inclusive option.

Southeast Asia lies between the Indian and Pacific Oceans, and its geostrategic importance in every period has come from that position and its maritime character. The Strait of Malacca, between the Malay peninsula and Sumatra, with the Sunda and Lombok straits, carries a large share of the world's seaborne trade, and control of these chokepoints has drawn Indian, Chinese, Arab, European and later American interest.

• Option (d) is correct because it is the only explanation that holds over space and time, as the stem demands.
• Option (a) is wrong because the Second World War was an episode; the region was a Pacific war theatre because of its resources and sea lanes, the deeper reason in (d).
• Option (b) is wrong because the region does not lie between China and India in any sense that explains its global significance, and its importance predates and exceeds their relationship.
• Option (c) is wrong for the same reason as (a), the Cold War confrontations in Vietnam and elsewhere being episodes of limited duration. The official answer is (d). Elimination route: over space and time rules out every answer tied to a single period.

Trans fats are unsaturated fats with at least one double bond in the trans configuration, which makes the molecule straight and so solid at room temperature; most in the diet come from the partial hydrogenation of vegetable oils into vanaspati and margarine.

• Statement 1 is correct: a claim of no trans fats signifies, above all, that the products are not made with partially hydrogenated oils, the principal source.
• Statement 2 is incorrect: the claim says nothing about animal fats; butter, ghee and tallow are saturated fats and are not excluded, and ruminant fat even contains small amounts of natural trans fats, so the statement confuses the type of fat with its source.
• Statement 3 is correct: trans fats raise low density lipoprotein cholesterol and lower high density lipoprotein cholesterol, so their absence means the oils are less likely to damage cardiovascular health.
• Statements 1 and 3 being correct, the official answer is (c). Since this paper, FSSAI has limited industrial trans fat in oils and fats to 2 percent from January 2022. Elimination route: knowing that trans fats come from hydrogenation and harm the heart confirms statements 1 and 3, and only (c) has both.

The National Rural Employment Guarantee Act, 2005, renamed the Mahatma Gandhi National Rural Employment Guarantee Act in 2009, guarantees at least one hundred days of wage employment in a financial year to every rural household whose adult members volunteer for unskilled manual work. The guarantee is universal and self selecting: any rural household may register with the gram panchayat for a job card, and any adult member may demand work, to be provided within fifteen days or an unemployment allowance is payable. Only those who need work will turn up for hard manual labour at the minimum wage, so no means test is required.

• Option (d) is correct for this reason.
• Option (a) is wrong because, although Scheduled Caste and Scheduled Tribe households are among the main participants, the entitlement is not confined to them.
• Option (b) is wrong because the Act deliberately does not use the below poverty line list, whose errors of exclusion were well known.
• Option (c) is wrong because backward community status is not a criterion either. The official answer is (d). Elimination route: the word guarantee and the Act's demand driven design point to the universal option.

India's Look East Policy was launched in 1991 under Prime Minister P. V. Narasimha Rao, after the economic crisis and the end of the Cold War, to build economic, strategic and political ties with Southeast and East Asia.

• Statement 1 is correct: the policy aimed to establish India as an important regional player in East Asia, moving from sectoral dialogue partnership with ASEAN in 1992 to full dialogue partnership in 1995, summit level partnership in 2002 and the East Asia Summit from 2005.
• Statement 2 is incorrect: the end of the Cold War was part of the context, but plugging a vacuum it left was not an objective; India had never been a party to the superpower contest in the region and did not seek to replace either power.
• Statement 3 is correct: restoring the historical and cultural links of Buddhism, trade and the spread of Indian scripts, epics and art across Southeast Asia was an explicit theme.
• Statements 1 and 3 being correct, the official answer is (b). Since then the policy has been upgraded to the Act East Policy, announced in 2014.

Under Article 75(3) the Council of Ministers is collectively responsible to the Lok Sabha, and holds office only while it commands that House's confidence. The Budget is the central statement of Government policy, and its defeat in the Lok Sabha is treated by convention as a loss of confidence, so the Prime Minister submits the resignation of the whole Council of Ministers.

• Option (d) is correct for this reason.
• Option (a) is wrong because a Government that has lost the confidence of the House does not simply revise and reintroduce a defeated budget; only a new Government with a majority can carry the financial business.
• Option (b) is wrong because the Rajya Sabha can only recommend changes to money bills within fourteen days, and demands for grants are voted by the Lok Sabha alone under Article 113.
• Option (c) is wrong because responsibility is collective: the defeat of the Budget is the defeat of the Government, not of the Finance Minister. The official answer is (d). Elimination route: collective responsibility to the Lok Sabha is the governing principle, and only (d) applies it.

The Fundamental Duties were added as Part IVA, Article 51A, by the Forty second Amendment Act, 1976, on the Swaran Singh Committee's recommendation. At the date of this paper there were eleven, the eleventh, on education for children aged six to fourteen, added by the Eighty sixth Amendment in 2002.

• Option (b) is a fundamental duty: clause (h) requires every citizen to develop the scientific temper, humanism and the spirit of inquiry and reform.
• Option (c) is a fundamental duty: clause (i) requires every citizen to safeguard public property and abjure violence.
• Option (d) is a fundamental duty: clause (a) requires every citizen to abide by the Constitution and respect its ideals and institutions, the national flag and the national anthem.
• Option (a) is not a fundamental duty and is the answer: voting is a right of every adult citizen under Article 326 and the Representation of the People Act, 1951, not a duty; the Swaran Singh Committee had suggested a duty to vote and pay taxes, but it was not adopted. The official answer is (a). Elimination route: India has no compulsory voting, so (a) is the odd one out.

The Finance Commission is a quasi judicial body constituted by the President every five years under Article 280. It recommends the distribution between the Union and the States of the net proceeds of shareable taxes and the allocation of the States' share among them, the principles governing grants in aid to the States under Article 275, and measures to augment a State's Consolidated Fund to supplement the resources of panchayats and municipalities. At the date of this paper the Thirteenth Finance Commission, chaired by Vijay Kelkar, had made its recommendations for 2010 to 2015.

• Option (a) is wrong because attracting foreign capital for infrastructure is no part of its remit.
• Option (b) is wrong because it distributes finances between the Union and the States, not among public sector undertakings.
• Option (c) is wrong because transparency of financial administration belongs to the Comptroller and Auditor General and Parliament's financial committees. None of the three being correct, the official answer is (d). Elimination route: knowing that the Commission deals with Union State fiscal transfers eliminates (a), (b) and (c) at once.

The Universal Declaration of Human Rights was adopted by the United Nations General Assembly in Paris on 10 December 1948. Though a declaration rather than a treaty, it underlies the two International Covenants of 1966.

• Statement 1 is a right under the Declaration: Article 26 gives everyone the right to education, free at least in the elementary stages and compulsory at the elementary level.
• Statement 2 is a right: Article 21(2) gives everyone the right of equal access to public service in his country, alongside the right in Article 21(1) to take part in government.
• Statement 3 is a right: Article 25(1) gives everyone the right to a standard of living adequate for the health and well being of himself and his family, including food, clothing, housing and medical care. All three being rights under the Declaration, the official answer is (d). The item is moderate because the Declaration is remembered chiefly for its civil liberties, though its social and economic rights are its distinctive feature.

A harmful algal bloom is a rapid growth of microscopic algae, such as certain dinoflagellates, diatoms and cyanobacteria, to densities that discolour the water, deplete its oxygen or produce toxins that kill fish and contaminate shellfish. Blooms occur when nutrients, chiefly nitrogen and phosphorus, become abundant in sunlit water.

• Statement 1 is correct: estuaries deliver nutrients from rivers carrying sewage, effluent and fertiliser to coastal seas, and this eutrophication is the main driver of more frequent blooms along Indian coasts.
• Statement 2 is correct: monsoon run off washes fertiliser, manure and soil into rivers and the sea, a seasonal pulse of nutrients often followed by blooms.
• Statement 3 is correct: upwelling brings nutrient rich deep water to the surface and, though natural, can trigger intense blooms, including Noctiluca in the Arabian Sea after the monsoon upwelling off the south west coast. All three being causative factors, the official answer is (d). Elimination route: all three add nutrients to surface waters, and the question asks for causes, not only for pollution.

The carbon cycle moves carbon between the atmosphere, living things, the oceans and the rocks, and each process either releases carbon dioxide to the air, as a source, or removes it, as a sink.

• Statement 1, photosynthesis, is a sink and does not add carbon dioxide: plants, algae and cyanobacteria fix it into carbohydrate using light energy, releasing oxygen.
• Statement 2, respiration, adds carbon dioxide: plants, animals and micro organisms oxidise organic compounds for energy, producing carbon dioxide and water.
• Statement 3, the decay of organic matter, adds carbon dioxide: decomposers such as bacteria and fungi break down dead tissue and, through their own respiration, return its carbon to the air as carbon dioxide, or as methane where oxygen is absent.
• Statement 4, volcanic action, adds carbon dioxide: volcanoes release carbon from the Earth's interior, the main natural geological source over long periods.
• Statements 2, 3 and 4 adding carbon dioxide, the official answer is (c). Elimination route: photosynthesis is the textbook sink, and (c) is the only option that leaves it out while keeping the other three.

The four multilateral export control regimes are the Nuclear Suppliers Group, the Missile Technology Control Regime, the Australia Group and the Wassenaar Arrangement, informal groupings of states coordinating national export controls.

• Statement 1 is incorrect. Its first half is accurate: the Australia Group, formed in 1985 after Iraq's use of chemical weapons against Iran, is an informal arrangement harmonising export controls so that exports do not contribute to chemical and biological weapons. But the Wassenaar Arrangement, established in 1996 as successor to the Cold War Coordinating Committee, is not a formal group under the OECD, and it covers conventional arms and dual use goods and technologies.
• Statement 2 is incorrect: both groupings are dominated by European states, with the United States, Canada, Japan and Australia, neither predominantly Asian or African. Neither statement being correct, the official answer is (d). Since then India has joined the Missile Technology Control Regime in 2016, the Wassenaar Arrangement in December 2017 and the Australia Group in January 2018, while its application to the Nuclear Suppliers Group remains pending. Elimination route: the OECD has no arms control function, which defeats statement 1.

Water behaves anomalously between 0 and 4 degrees Celsius: it contracts on heating from 0 to 4 degrees and expands beyond, so its density is greatest at about 4 degrees. As a lake cools in winter, the surface water becomes denser and sinks until the whole body reaches 4 degrees; further cooling makes the surface water lighter, so it stays on top, cools to 0 degrees and freezes, while the densest water remains at the bottom.

• Option (c) is correct because the maximum density of water at 4 degrees is the governing reason the bottom stays liquid.
• Option (a) is true, the ice slowing further freezing, but it is a consequence of the anomaly: without it, the coldest water would sink and lakes would freeze from the bottom up.
• Option (b) is wrong because the surface does lose heat to colder air; that is why it freezes.
• Option (d) falls because (c) is correct. The official answer is (c). Elimination route: the anomalous expansion of water is a standard NCERT example, and a candidate who recalls it chooses (c) over the partial explanation in (a).

The habitat described is the Rann of Kutch in Gujarat, a flat of saline mudflats and sandy islands called bets, and the animal is the Indian wild ass, Equus hemionus khur, option (b). Its last population lives in and around the Little Rann, where the Indian Wild Ass Sanctuary was notified in 1973. The adult has no natural predator of consequence in the Rann, the wolf taking only the occasional foal, so its threats have come from habitat loss: salt pans, the spread of Prosopis juliflora, grazing pressure, canal seepage and disease.

• Option (a) is wrong because the Indian wild buffalo, Bubalus arnee, lives in tall wet grasslands and swamps in Assam and central India and is preyed upon by tigers.
• Option (c) is wrong because the wild boar is a widespread, adaptable animal, not threatened and heavily preyed upon.
• Option (d) is wrong because the chinkara lives in the arid Thar and Deccan scrub, not the saline Rann specifically, and is hunted by wolves and dogs. The official answer is (b). Since this paper the Gujarat Forest Department's censuses have recorded a steady rise in the population.

Both phases belong to the El Nino Southern Oscillation of the equatorial Pacific. In El Nino the trade winds weaken and warm water spreads east, so the central and eastern equatorial Pacific turns unusually warm; in La Nina the trades strengthen and the same region turns unusually cold, deepening rainfall over Australia and southeast Asia.

• Statement 1 is incorrect because it places La Nina in the equatorial Indian Ocean. La Nina is a cooling of the equatorial Pacific, not the Indian Ocean, whose own oscillation is the Indian Ocean Dipole.
• Statement 2 is incorrect because La Nina does affect the monsoon: it is generally associated with normal or above normal rainfall over India, just as El Nino is associated with weak monsoons and droughts, as in 2009. Neither statement being correct, the official answer is (d). A candidate who recalls that both phases are Pacific events rejects statement 1, and anyone who knows that La Nina years tend to bring a good monsoon rejects statement 2.

The Permanent Settlement of 1793 fixed the land revenue of Bengal and Bihar in perpetuity and recognised the zamindars as proprietors, with the right to sell, mortgage and bequeath the land. The standard texts trace the rise in litigation to this marketable private property in land and the rigid sale law: an estate in arrears by the appointed date was auctioned, so titles changed hands rapidly and disputes over ownership, boundaries, sales and tenants' dues multiplied.

• Option (a) is wrong because the Regulations of 1793 did not set out to strengthen the zamindar against the ryot; the powers of distraint that did so came later, in the Haftam Regulation of 1799 and the Panjam Regulation of 1812.
• Option (b) is wrong because the Company was already the revenue authority as Diwan from 1765.
• Option (c) is wrong because the Cornwallis Code reorganised the courts but did not make them efficient; they were soon clogged with arrears, a consequence of litigation, not its cause. The official answer is (d).
• Option (a) tempts a candidate who remembers only that the settlement favoured zamindars.

Gandhi gave the call of Do or Die at the Gowalia Tank session of the All India Congress Committee in Bombay on 8 August 1942, but early on 9 August he and the entire Congress leadership were arrested under Operation Zero Hour. The movement therefore ran without its leaders, so (b), that it was led by Mahatma Gandhi, is the observation the examiner treats as not true.

• Option (c) is true: with the leaders in jail, the rising was spontaneous and decentralised, carried by students, peasants and local leaders, with parallel governments in Ballia, Tamluk and Satara.
• Option (d) is broadly true: labour struck in places such as Jamshedpur, Ahmedabad and Bombay, but the working class in general was held back, partly because the Communist Party, backing the war as a People's War, stayed away.
• Option (a) is the delicate one: despite sabotage of railways, telegraph lines and police stations, it was launched as a non violent struggle and Gandhi refused to condemn it as violent, so the examiner treats it as true. The official answer is (b). The arrests of 9 August alone rule out Gandhi's leadership of the actual movement.

The tribal revolts of the nineteenth century, from the Kol rising of 1831 and the Santhal hool of 1855 to the Munda ulgulan of 1899 to 1900, had different immediate causes, and the question asks for the factor common to all.

• Option (d) is that factor and is the official answer. Colonial rule broke the old tribal agrarian order everywhere: collective ownership of land gave way to private property and revenue, shifting cultivation and forest use were restricted by forest laws, and outsiders took over land, disrupting the whole economy of tribal society.
• Option (a) is a real cause in many cases, but only one element of that larger disruption, not the common denominator.
• Option (b) is wrong as a common factor because missionary activity mattered only in some areas, such as Chota Nagpur in the Munda case, and elsewhere was no grievance at all.
• Option (c) describes the dikus, the moneylenders, traders and revenue farmers central to the Santhal and Munda risings, but they were the agents of the disruption.
• Options (a), (b) and (c) each name a cause found in some revolts; (d) names the condition all shared.

India's early contacts with southeast Asia, which carried traders, Brahmin priests and Buddhist monks to Funan, Champa, Srivijaya and Java from the early centuries of the Common Era, rode on the monsoon. The south west monsoon from about June to September blows ships eastward across the Bay of Bengal, and the north east monsoon of winter brings them back, so sailors could cross and return within a year on predictable winds. That regularity is the most convincing explanation of the Bay of Bengal's pre eminence in early maritime history, and option (c) is the official answer.

• Option (a) is wrong because there is no evidence that Indian shipbuilding was superior; the Arabs, the Chinese and the southeast Asian peoples themselves were accomplished shipbuilders.
• Option (b) is wrong because of the word always: some southern dynasties, such as the Pallavas and the Cholas, did patronise trade and religious missions, but constant patronage across all rulers is too sweeping a claim.
• Option (d) falls with (a) and (b). The absolute words, better than other countries and always, mark (a) and (b) as overstatements.

Bluetooth and Wi-Fi are both radio technologies in the unlicensed industrial, scientific and medical band. Bluetooth works in the 2.4 GHz band, hopping among channels between 2.402 and 2.480 GHz, while Wi-Fi under the IEEE 802.11 standards uses either 2.4 GHz (802.11b, g and n) or 5 GHz (802.11a and n).

• Option (a) states exactly this and is correct.
• Option (b) is wrong on both halves: Bluetooth is designed for a wireless personal area network of a few metres, linking a phone to a headset, and Wi-Fi is the standard for wireless local area networks, not wide area networks, which are served by cellular technologies.
• Option (c) is wrong because neither needs line of sight; radio waves at these frequencies pass through walls and bodies, with some loss. Line of sight belongs to infrared links such as the old IrDA ports and television remotes, the trap of the option.
• Option (d) fails because (b) is wrong. The official answer is (a). Since this paper Wi-Fi has also moved into the 6 GHz band with Wi-Fi 6E.

Micro irrigation, drip and sprinkler, delivers water in small measured amounts close to the root zone.

• Statement 1 is correct. Because little is lost to deep percolation, nutrients applied with it are not leached away, and fertigation, feeding soluble fertiliser through the drip lines, makes nutrient use markedly more efficient.
• Statement 2 is incorrect. Dry land farming is by definition farming in low rainfall areas largely without irrigation, depending on moisture conservation through contour bunding, mulching, drought tolerant crops and watershed management; micro irrigation is not the only means, and many dry land systems have no irrigation at all.
• Statement 3 is correct. By cutting the water a crop needs, often by a third to a half compared with flood irrigation, micro irrigation reduces groundwater pumping and so can check the fall of the water table in overdrawn regions such as parts of Punjab, Gujarat and Tamil Nadu.
• Statements 1 and 3 being correct, the official answer is (c). The absolute word only in statement 2 removes (b) and (d).

Home Charges were the payments made in Britain out of Indian revenues and the core of the drain of wealth described by Dadabhai Naoroji and R. C. Dutt. They comprised dividends to East India Company shareholders until 1874, interest on the London debt, the cost of the India Office and the Secretary of State's establishment, War Office payments for British troops in India, stores bought in Britain, and the salaries, leave allowances and pensions of British personnel paid in England.

• Statement 1 is correct, the India Office being maintained entirely from Indian revenues.
• Statement 2 is correct, the salaries and pensions of British personnel being among the largest heads.
• Statement 3 is treated as incorrect. Many campaigns beyond India's borders, in Afghanistan, Burma, Abyssinia and elsewhere, were charged to Indian revenues, to bitter nationalist protest, but these were met from the military budget in India and are counted by the standard texts as a separate grievance.
• Statements 1 and 2 being correct, the official answer is (b).
• Statement 3 is the trap, tempting a candidate who knows that India paid for imperial wars towards (d).

The Kheda satyagraha of 1918 was Gandhi's first true non cooperation movement among the peasants of Gujarat. Kheda's crops failed in 1917 to 1918 owing to drought and excessive late rain, and under the Revenue Code a yield below a quarter of normal entitled the cultivators to remission of land revenue. The administration refused to suspend or remit the revenue, and Gandhi, with Vallabhbhai Patel, Indulal Yagnik and others, organised the peasants to withhold payment; the government finally agreed to suspend it for those who could not pay.

• Statement 1 is correct for this reason.
• Statement 2 is incorrect. Gujarat, then part of the Bombay Presidency, was under the ryotwari system, and there was no proposal to introduce the Permanent Settlement, which had been confined to Bengal, Bihar, parts of Orissa and northern Madras and was not extended to new areas after the early nineteenth century.
• Statement 1 being correct and statement 2 incorrect, the official answer is (a). A candidate who recalls that the Permanent Settlement was an eastern system of 1793 rejects statement 2 at once.

The question tests ecosystem services, the benefits living diversity provides to people.

• Statement 1 is correct: soil is formed not only by the weathering of rock but by lichens, mosses, plant roots, earthworms, termites, fungi and bacteria, which break rock down and add humus.
• Statement 2 is correct: vegetation and roots bind soil and break the force of rain and wind, so the loss of plant diversity on slopes and in catchments is a leading cause of erosion.
• Statement 3 is correct: decomposers, the bacteria, fungi and invertebrates of soil and water, break down dead matter and waste and return nutrients to the cycle, the basis of natural waste recycling and of sewage treatment.
• Statement 4 is correct: bees, butterflies, moths, birds and bats pollinate a large share of the world's crops, and the decline of pollinators is a recognised threat to food security. All four statements being correct, the official answer is (d). The item has no trap; it rewards recognising that supporting and regulating services are as much part of biodiversity's value as food.

Aspartame is the methyl ester of a dipeptide of aspartic acid and phenylalanine. In the gut it is broken down completely into these two amino acids and a little methanol, metabolised like those from any protein, so it yields about 4 kilocalories per gram, the same as protein. It works as a low calorie sweetener because it is about 200 times sweeter than sucrose, so little is needed that its calories are negligible.

• Option (d) states this and is correct.
• Option (a) is wrong because aspartame is readily digested by the body's peptidases and esterases.
• Option (b) is wrong because food processing does not make it resistant to oxidation; it loses sweetness on prolonged heating, making it unsuitable for baking.
• Option (c) is wrong because its metabolites, the amino acids, do yield calories. The official answer is (d). The stem says aspartame provides calories like other amino acids, which rules out (a), (b) and (c). Since this paper the International Agency for Research on Cancer classed aspartame as possibly carcinogenic in 2023, while the expert committee of FAO and WHO kept its acceptable daily intake unchanged.

The early nationalists of the Moderate phase believed that the British Parliament and public, once informed, would redress Indian grievances, and carried their case to London. The British Committee of the Indian National Congress was set up in 1889 with Sir William Wedderburn as chairman. In 1893 Wedderburn and W. S. Caine, both members of the House of Commons, formed the Indian Parliamentary Committee of members sympathetic to India to raise Indian questions and press for political reforms in Parliament; Dadabhai Naoroji, elected for Central Finsbury in 1892, worked with it.

• Option (a) states this purpose and is correct.
• Option (b) is wrong because the Committee was not formed to campaign for Indians in the judiciary; entry into the services was argued mainly through the demand for simultaneous Indian Civil Service examinations.
• Option (c) is wrong because independence was on nobody's agenda in 1893; the Moderates sought reforms within British rule.
• Option (d) is wrong because getting Indians elected to Parliament was never its object, though Naoroji's election had just shown it possible. The official answer is (a). Placing 1893 in the Moderate phase rejects (c).

• Statement 1 is correct. A compact fluorescent lamp is a gas discharge tube: an electric current through mercury vapour produces ultraviolet light, which a phosphor coating converts to visible light. A light emitting diode is a semiconductor device in which electrons and holes recombine at a p n junction and release light, with no gas, filament or mercury.
• Statement 2 is incorrect because it reverses the facts: a CFL typically lasts about 8,000 to 10,000 hours, while a good LED lamp lasts 25,000 hours or more.
• Statement 3 is correct. An LED gives more lumens per watt than a CFL and wastes less energy as heat, so a CFL is less efficient.
• Statements 1 and 3 being correct, the official answer is (c). Knowing LEDs as the longer lasting, more efficient technology rejects statement 2 and confirms statement 3. Since this paper the UJALA programme of 2015 has replaced CFLs with LED bulbs as the lamp the Government distributes, and CFLs, which contain mercury, have largely left the market.

Oilzapper is a bioremediation product developed in India by The Energy and Resources Institute with Indian Oil Corporation. It is a consortium of bacterial strains, isolated from oil contaminated sites, that feed on the hydrocarbons of crude oil and oily sludge and break them down into carbon dioxide and water. The bacteria are supplied immobilised on powdered corn cob, spread on contaminated soil or an oil slick, and the method has been used to clean oily sludge at refineries and sites polluted by spills.

• Option (a) states this and is correct; it is eco friendly because it uses naturally occurring microbes and leaves no toxic residue, unlike chemical dispersants.
• Option (b) is wrong because it cleans up oil rather than finding it.
• Option (c) is wrong because it is a microbial product, not a crop, and has nothing to do with biofuel maize.
• Option (d) is wrong because fighting oil well fires needs explosives, foam and capping, not microbes. The official answer is (a). Only (a) is about removing oil already released, so knowing that bacteria can digest oil is enough.

Gandhi read John Ruskin's Unto This Last, essays of 1860 on political economy, on a train from Johannesburg to Durban in 1904, and wrote that it made him transform his life. His three lessons were that the good of the individual is contained in the good of all; that a lawyer's work has the same value as the barber's, since all have the same right to earn a livelihood; and that a life of labour, of the tiller of the soil and the handicraftsman, is the life worth living. He translated it into Gujarati in 1908 as Sarvodaya, the welfare of all, a central idea of his.

• Option (b) is the first and principal lesson and is correct.
• Option (a) is wrong because the duty of educated men to uplift the poor is not Ruskin's message; the book attacks the political economy of self interest and holds that wealth must serve life.
• Option (c) is wrong because celibacy and spiritual pursuit come from Gandhi's own vows and religious sources, not from Ruskin.
• Option (d) falls with them. The official answer is (b). The word Sarvodaya alone leads to the answer.

Usha Mehta, a student of twenty two in Bombay, is remembered for the secret Congress Radio of the Quit India Movement. With the Congress leaders arrested on 9 August 1942 and the press censored, she and colleagues including Vithalbhai Jhaveri and Chandrakant Jhaveri set up an underground transmitter whose first broadcast went out on 14 August 1942 as the Congress Radio calling from somewhere in India. Ram Manohar Lohia and other underground leaders spoke on it, and it carried news the government suppressed. It moved from place to place until the police found it in November 1942; she was sentenced to four years' imprisonment.

• Option (a) is therefore correct.
• Option (b) is wrong because the Second Round Table Conference of 1931 was attended by Gandhi as the sole Congress representative, with Sarojini Naidu among the other Indian delegates.
• Option (c) is wrong because the Rani of Jhansi Regiment of the Indian National Army was led by Captain Lakshmi Swaminathan.
• Option (d) is wrong because she had no role in forming the Interim Government of 1946. The official answer is (a). She was awarded the Padma Vibhushan in 1998.

Blu-ray takes its name from the blue violet laser of 405 nanometres it uses to read data, against the red laser of 650 nanometres for DVDs; the shorter wavelength allows a smaller spot, smaller pits and tighter tracks, so far more data fit on the same disc.

• Statement 1 is correct. DVD Video carries standard definition video of 480 or 576 lines, while Blu-ray was designed for high definition video up to 1080 lines.
• Statement 2 is correct. A single layer Blu-ray disc holds 25 GB and a dual layer one 50 GB, against 4.7 GB and 8.5 GB for a DVD.
• Statement 3 is incorrect. Both formats, like the compact disc, are 120 mm in diameter and 1.2 mm thick, so the same drives and cases handle them; what differs is the depth of the data layer, about 0.1 mm below the surface on Blu-ray against 0.6 mm on DVD.
• Statements 1 and 2 being correct, the official answer is (b). A candidate who knows that Blu-ray discs fit the same trays as DVDs and CDs will doubt that one is twice as thick, rejecting statement 3.

The Nehru Report of August 1928 was drafted by a committee of the All Parties Conference under Motilal Nehru, in answer to Lord Birkenhead's challenge to Indians to produce an agreed constitution after the appointment of the all white Simon Commission.

• Statement 1 is incorrect. The Report asked for dominion status within the Commonwealth, not complete independence; younger leaders such as Jawaharlal Nehru and Subhas Chandra Bose objected to precisely this, and the Lahore session of December 1929 adopted Purna Swaraj as the goal of the Congress.
• Statement 2 is correct. The Report rejected separate electorates and proposed joint electorates, with reservation of seats for Muslims at the Centre and in provinces where they were a minority, though not in Bengal and Punjab, where they were a majority.
• Statement 3 is correct. The Report contained nineteen fundamental rights, including equal rights for women, the right to form unions and universal adult suffrage.
• Statements 2 and 3 being correct, the official answer is (b). The date of 1929 for complete independence is enough to reject statement 1, leaving only (b).

Orchids flourish in warm, humid, shaded conditions with high rainfall and moderate temperatures, and the richest orchid flora in India is in the north east and the Himalayan foothills. Arunachal Pradesh alone has over 600 of the roughly 1,300 orchid species recorded in India and is often called the orchid state of the country, with an orchid research centre at Tipi and an orchid sanctuary at Sessa. Its heavy rainfall, high humidity and wide range of altitudes let many species be grown in natural conditions without costly greenhouses, which makes production cheap and an export oriented floriculture industry possible.

• Option (b) is therefore the official answer.
• Option (a) is wrong because Andhra Pradesh has a largely hot climate with a dry interior, where orchids need controlled conditions.
• Option (c) is wrong because Madhya Pradesh has a hot, dry summer and a continental climate unsuited to most orchids.
• Option (d) is wrong because Uttar Pradesh, in the Gangetic plain, has extremes of heat and cold and low humidity outside the monsoon. The answer follows from recognising the one north eastern State among the four.

The Metropolitan Planning Committee was introduced by the Constitution (Seventy fourth Amendment) Act, 1992, in Part IXA.

• Statement 1 is correct. Article 243ZE provides that every Metropolitan area, one with a population of ten lakh or more under Article 243P, shall have a Metropolitan Planning Committee to prepare a draft development plan, leaving its composition and chairperson to State law, with at least two thirds of the members be elected from the elected members of the municipalities and the chairpersons of the panchayats in the area.
• Statement 2 is correct, the draft development plan being the very function Article 243ZE assigns, forwarded by the chairperson to the State Government.
• Statement 3 is incorrect. The Committee is a planning body; it does not implement Government sponsored schemes, which remain with the municipalities, development authorities and State line departments, and the words sole responsibility make the statement impossible.
• Statements 1 and 2 being correct, the official answer is (a).
• Statement 3 falls as an absolute claim, and the Metropolitan Planning Committee of Article 243ZE, like the District Committee of Article 243ZD, is a constitutional body.

A vote on account is a grant made by the Lok Sabha under Article 116 to meet expenditure for part of a financial year pending the voting of the demands for grants and the Appropriation Bill. An interim budget is a full statement of estimated receipts and expenditure presented by a government unable to present a full budget, typically in an election year, leaving that to the new government.

• Statement 1 is incorrect. Regular governments took a vote on account yearly when the budget was presented in late February, as the demands could not pass before 1 April, and an interim budget is presented by an outgoing regular government before a general election, not only by a caretaker one.
• Statement 2 is correct. A vote on account deals only with expenditure, authorising withdrawal from the Consolidated Fund, while an interim budget sets out both receipts and expenditure, with an accompanying vote on account.
• Statement 2 alone being correct, the official answer is (b). Since this paper the Union Budget has been presented on 1 February from 2017, so that a vote on account is now needed only in election years.

The International Monetary Fund, created at Bretton Woods in 1944, is a cooperative of member countries that pool resources through their quota subscriptions. Under its Articles of Agreement it lends only to its members, to help them meet balance of payments difficulties, through arrangements such as stand by arrangements, the Extended Fund Facility and concessional facilities for low income members.

• Option (c) states this and is correct.
• Option (a) is wrong because a country must first join, accepting the obligations of membership and paying its quota, before it can draw on the Fund.
• Option (b) is wrong because the Fund lends to all members regardless of development; most of its lending has gone to developing and emerging economies, along with advanced economies in crisis such as Greece, Ireland and Portugal in 2010 and 2011.
• Option (d) is wrong because the Fund deals with a member government through its fiscal agency, often its central bank, but the borrower is the member country, not the bank. The official answer is (c). The IMF's lending to Greece in 2010 makes the restriction to developed countries in (b) plainly wrong.

Mangroves are salt tolerant trees and shrubs of the intertidal zone, and their protective role comes from their roots. Stilt roots, prop roots and buttresses spread widely and anchor them in soft mud, and breathing roots called pneumatophores rise out of the mud in dense ranks. This tangle is not uprooted by storms and tides; it slows waves, absorbs the energy of storm surges and tsunamis and traps sediment, so settlements behind a broad mangrove belt suffered less in 2004, as near Pichavaram in Tamil Nadu.

• Option (d) states this and is correct.
• Option (a) is wrong because mangroves do not protect by keeping people away; communities live around them, and it is the vegetation that absorbs the wave.
• Option (b) is wrong because food and medicines after a disaster are an incidental benefit, not a safety hedge.
• Option (c) is wrong because most mangroves are of modest height and no shelter; standing in a tidal forest during a tsunami would be dangerous. The official answer is (d). Root anchorage is the one fact needed; the other options describe side benefits or something mangroves do not do.

Jainism denies a creator god. It holds the universe eternal, without beginning or end, running by its own laws: the six substances, souls and the non living categories of matter, motion, rest, space and time, interact by fixed natural principles, and the soul's bondage through karma is itself a law, not a deity's will. The standard texts say that in Jain philosophy the world is created and maintained by universal law, which is option (a). The word created is loose, since the Jains hold the world uncreated, but universal law alone fits a universe without a creator.

• Option (b) is wrong because universal truth is not a cosmological principle in Jainism; its account of truth, anekantavada or many sidedness, is epistemological.
• Option (c) is wrong because right faith, among the three jewels, is a path to liberation for the individual, not a force that sustains the world.
• Option (d) is wrong because a universal soul is the Vedantic Brahman; Jainism recognises innumerable individual souls and no world soul. The official answer is (a). Ruling out (d) as the Upanishadic answer, a religion without a creator must rely on law.

Salinisation is land degradation common in irrigated arid and semi arid lands, as in parts of Punjab, Haryana and the Indira Gandhi Canal command. When irrigation water evaporates, the salts it carried are left behind and accumulate in the upper soil. Where sodium dominates, it disperses the fine clay particles, which clog the pores, destroy the crumb structure and form a hard crust; the soil becomes impermeable to water and air, roots cannot penetrate it and water stands on it.

• Option (b) states this and is correct, the sodic usar and reh lands of the Gangetic plain being the classic Indian example.
• Option (a) is wrong because salinisation reduces crop production, salts drawing water out of roots and being toxic in excess.
• Option (c) is wrong because a rising water table is a cause of salinisation, bringing salts up by capillary action, not an effect of it.
• Option (d) is wrong because salinisation leaves salts in the soil, as the stem says; it is waterlogging that fills the air spaces with water. The official answer is (b). The stem's salts left behind after evaporation rule out (c) and (d).

The Red Data Books, begun by the IUCN in the 1960s and now continued as the IUCN Red List of Threatened Species, record the conservation status of species, assessing each by population size, decline and range into categories from Least Concern through Vulnerable, Endangered and Critically Endangered to Extinct.

• Statement 2 is correct: the books are lists of threatened plant and animal species, their whole purpose.
• Statement 1 is incorrect. The books are not confined to endemic species, nor to those in biodiversity hotspots; they cover species everywhere, and the hotspot concept, developed by Norman Myers and taken up by Conservation International, classifies regions, not species.
• Statement 3 is incorrect. The books list species, not sites; protected areas are recorded separately, in the United Nations List of Protected Areas and the World Database on Protected Areas compiled by UNEP's World Conservation Monitoring Centre with the IUCN.
• Statement 2 alone being correct, the official answer is (b). Knowing that the Red List classifies species by threat confirms statement 2 and excludes both the regional idea of hotspots and the list of sites.

A teaser loan, offered by Indian banks mainly as a home loan, carries a low fixed rate for the first one to three years, then resets to a higher market rate.

• Statement 1 is correct. They draw in borrowers who can afford the opening instalments but may not afford the reset rates, and they resemble the subprime lending behind the American housing bubble and its collapse in 2007 and 2008, so banks are exposed to more defaults when rates reset. The Reserve Bank made this point in its monetary policy review of November 2010, raising the standard asset provision on teaser housing loans to 2 per cent over concern that borrowers might be unable to service them after the reset.
• Statement 2 is incorrect. In India teaser loans were mostly retail housing loans, offered by banks such as the State Bank of India from 2009, not loans to inexperienced entrepreneurs for manufacturing or export units, which are financed through priority sector and MSME credit lines.
• Statement 1 alone being correct, the official answer is (a). The word subprime in statement 1 points to housing, which rejects statement 2.

A satellite in orbit is in continuous free fall. Gravity pulls it towards the Earth's centre at every moment, but it moves sideways so fast, about 7.8 kilometres a second in low orbit, that the curved surface falls away beneath it at the same rate, so it keeps going round. Circular motion needs a centripetal acceleration of v squared over r towards the centre, and gravity supplies exactly this.

• Option (d) states this and is correct.
• Option (a) is wrong because gravity does exist at such distances: at the International Space Station's height, about 400 kilometres, it is still roughly ninety per cent of its surface value.
• Option (b) is wrong because the Moon's pull on an Earth satellite is tiny beside the Earth's and does not cancel it; if it did, the satellite would fly off straight.
• Option (c) is wrong because the launch vehicle gives the speed; in a circular orbit gravity acts at right angles to the motion and changes its direction, not its speed. The official answer is (d). The distinction between speed and acceleration is the whole of the item.

At the date of this paper the national accounts, on the 2004 to 2005 base, showed India's real GDP growing at about 9.5 per cent in 2005 to 2006, 9.6 per cent in 2006 to 2007 and 9.3 per cent in 2007 to 2008, then falling to about 6.7 per cent in 2008 to 2009 in the global financial crisis, then recovering to about 8 per cent in 2009 to 2010 and an advance estimate of 8.6 per cent for 2010 to 2011.

• Statement 1 is incorrect, because growth did not rise steadily: it fell in 2007 to 2008 and sharply in 2008 to 2009.
• Statement 2 is incorrect for the same reason: per capita income grows at roughly the rate of GDP less population growth of about 1.5 per cent a year, so it followed the same rise, dip and recovery. Neither statement being correct, the official answer is (d). The slowdown of 2008 to 2009 alone breaks the word steadily in both statements. Since then the base year has been revised to 2011 to 2012, which changed the series, but the dip of 2008 to 2009 remains.

Institutional credit to agriculture in India flows through commercial banks, cooperative banks and regional rural banks, with microfinance institutions a small addition. Since bank nationalisation in 1969 and the priority sector norms, commercial banks have become by far the largest. In 2009 to 2010 and 2010 to 2011 they accounted for roughly three quarters of the ground level credit to agriculture, against less than a fifth for the cooperative banks and about a tenth for the regional rural banks, as reported by NABARD and the Economic Survey.

• Option (a) is therefore correct.
• Option (b) is wrong because the cooperatives, once the main source of rural credit, have lost their lead since the 1970s, their share falling steadily despite their wide network of primary societies.
• Option (c) is wrong because the regional rural banks, set up from 1975 for small farmers and the rural poor, have always had a smaller share, being few and small.
• Option (d) is wrong because microfinance institutions lend mainly to women's groups, and their share in agricultural credit is marginal. The official answer is (a). Believing the cooperatives still dominate is the trap of (b).

Inclusive growth was the central theme of the Eleventh Five Year Plan, 2007 to 2012, Towards Faster and More Inclusive Growth: growth that spreads its benefits widely, reducing poverty and inequality across regions and social groups.

• Statement 1 is correct. Self Help Groups, promoted through the SHG Bank Linkage Programme of NABARD and the Swarnajayanti Gram Swarozgar Yojana, give the rural poor, especially women, credit and a livelihood, extending the benefits of growth to those excluded from formal finance.
• Statement 2 is correct. Micro, Small and Medium Enterprises are labour intensive and spread across towns and villages, employing far more people per unit of capital than large industry, so their growth widens employment and income.
• Statement 3 is correct. The Right of Children to Free and Compulsory Education Act, 2009, in force from 1 April 2010, guarantees free and compulsory schooling to every child from six to fourteen, and education is the surest long term means of including the poor in growth. All three statements being correct, the official answer is (d). The item has no trap; each is a recognised instrument of inclusion.

At the date of this paper the disinvestment policy, approved in November 2009, was to list profitable Central Public Sector Enterprises on the stock exchanges and sell minority stakes, the Government keeping at least 51 per cent of the equity and with it management control.

• Statement 1 is incorrect. The proceeds went into the National Investment Fund, set up in 2005, whose income was earmarked for social sector schemes and the capital investment of public enterprises; for 2009 to 2012 the whole proceeds could fund selected social sector programmes such as the employment guarantee scheme and urban renewal. Paying back external debt was never the stated purpose.
• Statement 2 is incorrect. The Government expressly intended to retain management control, the stated aims being to raise resources, give citizens a share in the ownership and improve their governance through listing. Neither statement being correct, the official answer is (d). Since then the policy has changed: the New Public Sector Enterprise Policy of 2021 provides for strategic disinvestment, with transfer of management control, in non strategic sectors, and Air India was sold to the Tata group in 2022.

Asteroids and comets are both small bodies left over from the formation of the solar system, but differ in make up and location.

• Statement 1 is correct. Asteroids are rocky or metallic bodies, sometimes called minor planets or planetoids, while comets are bodies of ice, frozen water, carbon dioxide, methane and ammonia mixed with dust and rock, the dirty snowballs of Fred Whipple's description.
• Statement 2 is incorrect. Asteroids are found mostly in the main belt between Mars and Jupiter, but comets come from the far outer solar system, the short period ones from the Kuiper Belt beyond Neptune and the long period ones from the Oort Cloud. No reservoir of comets lies between Venus and Mercury, where the heat of the Sun would quickly destroy them.
• Statement 3 is correct. Near the Sun a comet's ices vaporise, forming a glowing coma and tails of gas and dust pushed away from the Sun, while asteroids, having no ices, show no tail.
• Statements 1 and 3 being correct, the official answer is (b). Icy bodies stored close to the Sun are impossible, which rejects statement 2.

Economic growth raises incomes, employment and spending, and as demand rises faster than supply can expand, prices tend to rise. A moderate rate of inflation is therefore the normal companion of growth, even a lubricant of expansion; India's high growth years of 2005 to 2008 and the recovery of 2010 were years of rising prices.

• Option (b) is the official answer for this reason.
• Option (a) is wrong because deflation, a sustained fall in the price level, usually goes with weak demand, falling output and recession, as in the Great Depression or Japan's lost decade.
• Option (c) is wrong because stagflation is by definition stagnant output with high inflation, the opposite of growth, as in the oil shocks of the 1970s.
• Option (d) is wrong because hyperinflation, prices rising at many hundreds of per cent a year, destroys savings, investment and the use of money itself and goes with economic collapse, as in Germany in 1923 or Zimbabwe in 2008. The official answer is (b). Three options are conditions of economic distress, and only moderate inflation is consistent with expansion.

The Bank Rate is the standard rate at which the Reserve Bank of India buys or rediscounts bills of exchange and other commercial paper, in effect the rate at which it lends to banks for the long term. When it is lowered, banks borrow more cheaply and banks can lend more and at lower rates,, putting more money into the economy.

• Option (a) states this and is correct: lowering the Bank Rate is an expansionary step that increases liquidity.
• Option (b) is wrong because it describes the effect of raising the Bank Rate, which tightens liquidity.
• Option (c) is wrong because a change in the policy rate is meant precisely to change the cost and availability of money.
• Option (d) is wrong because lower rates reduce the return on deposits, if anything discouraging saving in them. The official answer is (a). At the date of this paper the Bank Rate had stood at 6 per cent since 2003,, the repo rate being the active signal; since February 2012 the Reserve Bank has aligned the Bank Rate with the Marginal Standing Facility rate, so it moves with the repo rate.

The westerlies blow from the subtropical high pressure belts towards the subpolar lows, between about 35 and 60 degrees of latitude in each hemisphere.

• Statement 1 is correct. In the southern hemisphere these latitudes are almost entirely ocean, interrupted only by the tip of South America, Tasmania and New Zealand, while in the northern hemisphere North America and Eurasia, with their mountains and seasonal pressure changes, create friction and break the winds up. Over the open Southern Ocean the westerlies blow strong and steady all year, earning the names Roaring Forties, Furious Fifties and Shrieking Sixties.
• Statement 2 is incorrect. The Coriolis force depends on the speed of the moving body and on the sine of the latitude, zero at the equator and greatest at the poles; it is equal in magnitude at the same latitude in both hemispheres and differs only in direction, deflecting winds right in the north and left in the south.
• Statement 1 alone being correct, the official answer is (a). That equality at the same latitude rules out statement 2.

Ships between India and East Asia now pass through the Strait of Malacca, between the Malay Peninsula and Sumatra, and round Singapore into the South China Sea.

• Statement 1 is incorrect. Deepening the Strait would let larger, deeper draught ships use it, its shallowest stretches limiting vessels to the Malaccamax size, but it would not shorten the route; ships would still sail round the tip of the Malay Peninsula, so neither distance nor sailing time would fall appreciably.
• Statement 2 is correct. The Isthmus of Kra, the narrowest part of the Malay Peninsula in southern Thailand, is only about 44 kilometres wide between the Andaman Sea and the Gulf of Thailand, formerly the Gulf of Siam. A canal across it, discussed since the seventeenth century, would let ships cut straight across instead of going round by Singapore, saving a detour commonly put at well over a thousand kilometres and two or three days of sailing.
• Statement 2 alone being correct, the official answer is (b). Deepening a channel changes the size of ships, not the length of the route, while a canal across a peninsula cuts it short.

Normal metabolism, especially the use of oxygen in the mitochondria, produces free radicals, reactive molecules such as the superoxide and hydroxyl radicals that carry an unpaired electron. They take electrons from neighbouring molecules and damage membranes, proteins and DNA, an oxidative stress linked to ageing, heart disease, cataract and some cancers. Antioxidants, such as vitamin C, vitamin E, beta carotene and the polyphenols and flavonoids of fruits and vegetables, neutralise free radicals by donating electrons without themselves becoming harmful, and so protect the cells.

• Option (c) states this and is correct.
• Option (a) is wrong because antioxidants do not activate enzymes for vitamin synthesis; the body cannot make vitamins C and E at all.
• Option (b) is wrong because the controlled oxidation of carbohydrates, fats and proteins is how the body gets its energy; antioxidants act on stray free radicals, not on this metabolism.
• Option (d) is wrong because antioxidants are not known to switch on genes to delay ageing; any effect on ageing comes through reduced oxidative damage. The official answer is (c). The term free radicals decides the item.

• Statement 1 is correct in the standard texts' reading. No structure at any Harappan site has been identified with certainty as a temple, and there are no royal tombs or palaces of a priestly ruler such as dominate Egypt and Mesopotamia. The cities had planned grids, granaries, drains, warehouses and workshops, and the evidence of religion, though clear, is limited: the mother goddess figurines, the seal of a horned figure in yogic posture often called proto Shiva, the worship of trees and animals, fire altars at Kalibangan and Lothal, and the Great Bath at Mohenjo daro, perhaps used for ritual bathing. Religion was present but did not dominate the urban scene.
• Statement 2 is correct. Harappans grew cotton, its earliest known use in the world, and wove it into textiles; a fragment of woven cotton cloth was found at Mohenjo daro, and spindle whorls are common. Both statements being correct, the official answer is (c).
• Statement 2 is well known and narrows the answer to (b) or (c), and statement 1 follows the NCERT view that the Harappan civilisation was not dominated by a priestly class.

The lower Gangetic plain, West Bengal and the delta of the Ganga and Brahmaputra, has a hot, humid climate, rainfall of 150 to 200 centimetres or more, high temperatures most of the year and fertile alluvium renewed by floods. Paddy needs about 25 degrees Celsius or more, heavy rainfall or standing water and alluvial soil; jute needs a hot, humid climate of 24 to 35 degrees, rainfall of 150 to 250 centimetres, well drained alluvium renewed yearly by floods, and plenty of soft water for retting the fibre. Both suit the region, and West Bengal is India's largest producer of rice and of jute.

• Option (c) is therefore the official answer.
• Option (a) is wrong because cotton needs moderate rainfall of 50 to 100 centimetres, a long frost free season and dry weather for picking, and black soils, so it is out of place in a humid delta.
• Option (b) is wrong because wheat needs a cool, moist growing season and a dry, sunny harvest, conditions of the upper and middle plain.
• Option (d) fails on both counts. A humid climate rules out wheat and cotton, leaving only (c).

The great desert belt of Africa and Eurasia, the Sahara, the Arabian desert and the deserts of Iran and the Thar, lies broadly between 15 and 30 degrees North.

• Statement 1 is correct. These latitudes are under the subtropical high pressure belt, where air that rose at the equator in the Hadley cell sinks back. Descending air is warmed by compression and dries, so clouds cannot form and rain is scarce; the offshore trade winds blowing towards the equator are dry too, and the deserts lie on the western sides and interiors of continents where the trades bring no moisture.
• Statement 2 is incorrect. Warm ocean currents increase evaporation and bring rain to the coasts they wash, as on the eastern sides of continents. Where currents contribute to deserts they are cold ones, such as the Canary current off the Sahara and the Benguela current off the Namib, which cool the air above them, stabilise it and prevent rain.
• Statement 1 alone being correct, the official answer is (a). Anyone who knows that warm currents make coasts wetter rejects statement 2.

The stratosphere extends from the tropopause, about 8 kilometres high at the poles and 18 at the equator, to about 50 kilometres. Its temperature stays constant in its lower part and then rises with height as ozone absorbs ultraviolet radiation, so warmer air lies over cooler, the reverse of the troposphere.

• Statement 1 is correct in the sense the examiner intends. Almost all the atmosphere's water vapour is in the troposphere, and the lower stratosphere is so dry that clouds and weather are practically absent, apart from rare polar stratospheric clouds at high latitudes, so there is no rain, hail or icing to trouble an aircraft.
• Statement 2 is correct. Because temperature does not fall with height, the stratosphere is stable and convection cannot develop; the air moves horizontally, so aircraft avoid the bumps of rising and sinking air. Both statements being correct, the official answer is (c). Long distance jets therefore cruise near the top of the troposphere and into the lower stratosphere, where the thin air also reduces drag. The slight overstatement in statement 1 does not alter the answer.

Both statements describe the main gradients of diversity on Earth.

• Statement 1 is correct. Biodiversity generally increases from the poles towards the equator: tropical forests, covering a small part of the land, hold more than half the world's species, and a hectare of Amazonian or southeast Asian rainforest may have more tree species than all of Europe. The usual reasons are the warm, stable climate with abundant energy and water, the long undisturbed history of the tropics, which escaped the glaciations of higher latitudes, and higher productivity supporting more niches.
• Statement 2 is correct. Climbing a mountain resembles moving towards the poles: temperature falls, the growing season shortens, soils thin and the area at each height decreases, so the number of species normally declines with altitude,. Some groups peak at middle elevations, but the word normally covers the exceptions. Both statements being correct, the official answer is (c). The item has no trap; the analogy between altitude and latitude makes statement 2 follow from statement 1.

The Himalaya does not end gently at its extremities but bends sharply around them, at the Nanga Parbat syntaxis in the west and the Namcha Barwa syntaxis in the east. A syntaxis is a sharp bend in the trend of mountain ranges, where folds and thrusts swing round a point, and these two are where the corners of the Indian plate drive into Asia. The Tsangpo flows east along the suture zone north of the Himalaya for over 1,000 kilometres, then at Namcha Barwa, 7,782 metres high, turns abruptly round the eastern syntaxis through one of the deepest gorges on Earth, entering India in Arunachal Pradesh as the Siang and flowing south and then west as the Brahmaputra.

• Option (b) names this cause and is the official answer.
• Option (a) is wrong because the uplift of the folded ranges explains their height, not the river's bend.
• Option (c) is wrong because it is too general: tectonic disturbance is true of the whole Himalaya and does not explain a turn at one point.
• Option (d) fails with (a). Without the technical term syntaxial bending the options look much alike.

Gujarat has all three characteristics.

• Statement 1: its northern part, Kutch with the Great and Little Rann and districts such as Banaskantha and Patan, is arid and semi arid, merging into the Thar.
• Statement 2: the black soil plains of central Gujarat and Saurashtra around Vadodara, Bharuch and towards Ahmedabad have long been a major cotton region, the old Broach cotton famous in the nineteenth century, and Gujarat had become the largest cotton producing State by the time of this paper after Bt cotton spread.
• Statement 3: its agriculture is dominated by cash crops, cotton, groundnut, castor, tobacco, cumin and other spices, which occupy more cropped area than foodgrains.
• Option (b) is therefore the official answer.
• Option (a) is wrong because the northern part of undivided Andhra Pradesh was not arid, and rice dominated.
• Option (c) is wrong because the semi arid north of Karnataka grows cotton in the north rather than the centre, and food crops such as ragi, jowar and rice dominate.
• Option (d) is wrong because Tamil Nadu has no arid north, and rice is its main crop. Only Gujarat, with Kutch, fits the arid north cleanly.

A Virtual Private Network extends an organisation's private network across a public network such as the internet. The user's device and the organisation's VPN gateway set up an encrypted tunnel, using protocols such as IPsec or SSL and TLS, so that data crossing the public internet cannot be read or altered, and the remote user works as if on the office network. It is virtual because no dedicated private line is laid, and private because encryption and authentication keep outsiders out.

• Option (b) states this and is correct.
• Option (a) is wrong because it leaves out the essential feature, the use of the public internet as the carrier, and is closer to an intranet.
• Option (c) is wrong because it describes cloud computing, in which users access a shared pool of computing resources, storage, servers and applications, from a service provider on demand.
• Option (d) fails because (b) is correct. The official answer is (b). Since this paper VPN services in India have been required by the directions of CERT-In of April 2022 to keep records of their users for five years.

Rita and dharma are two central moral ideas of the Vedic texts.

• Statement 1 is correct. Dharma, from the root dhri, to hold or sustain, came to mean the obligations a person owes to himself and to others, the duties of his station, which in the later Vedic and post Vedic texts became the duties of the varnas and stages of life: a conception of duty and its discharge, as the statement says.
• Statement 2 is correct. Rita in the Rig Veda is the cosmic order, the fundamental law governing the regular course of nature, the movement of sun and moon, the cycle of seasons and the flow of rivers, and also the moral order and the correct performance of the sacrifice. Varuna is called its guardian, ritasya gopa, and the gods themselves uphold it, so it is the fundamental moral law governing the universe and all it contains. Both statements being correct, the official answer is (c). Knowing rita as the Rig Vedic principle of cosmic order confirms statement 2, while statement 1 is the accepted meaning of dharma.