UPSC Civil Services · Past-year questions with answers

Statements 2 and 3 are correct, so the answer is (b). No presidential recommendation is needed to introduce a Constitution Amendment Bill, but the President must assent to it once passed, and there is no joint sitting for such bills. Under Article 368, an amendment can be initiated only by introducing a bill in either House of Parliament, and that bill may be moved by a minister or a private member without any prior recommendation of the President. Each House must pass it separately by a special majority — a majority of the total membership of the House and at least two-thirds of members present and voting — and Article 368 makes no provision for a joint sitting under Article 108 to resolve a deadlock, so a bill rejected by one House simply fails. The 24th Constitutional Amendment Act, 1971 made presidential assent to a Constitution Amendment Bill obligatory: the President can neither withhold assent nor return the bill for reconsideration. Bills touching federal provisions additionally need ratification by the legislatures of half the states by simple majority.

Prepared with PrepKar AI and checked; it may contain errors.

Answer c: statements 1 and 3 are correct. A rising NEER does mean the rupee is appreciating, and a domestic-inflation gap does widen the NEER–REER divergence, but a rising REER signals a loss, not a gain, in trade competitiveness. NEER is the trade-weighted average value of the rupee against a basket of partner currencies, so a higher NEER means each rupee buys more foreign currency — an appreciation (statement 1 correct). REER is NEER adjusted for relative price levels; when REER rises, Indian goods become dearer relative to competitors', so exports lose price competitiveness — statement 2 has the direction reversed. Because REER = NEER × (domestic prices / partner prices), higher domestic inflation than partners' pushes REER above NEER even when NEER is flat or falling, so the two indices diverge (statement 3 correct). The RBI publishes 6-currency and 40-currency NEER/REER indices monthly in its Bulletin.

Prepared with PrepKar AI and checked; it may contain errors.

Option (c) — statements I and III are correct. An Ordinance has the same force as an Act, so it can amend a Central law and can be given retrospective effect; but it cannot abridge a Fundamental Right, because an Ordinance is 'law' under Article 13. Article 123 says an Ordinance promulgated by the President 'shall have the same force and effect as an Act of Parliament', so its power is co-extensive with Parliament's legislative power — it can amend or repeal a Central Act, subject to the same limits. Because Article 13(3)(a) defines 'law' to include an ordinance, Article 13(2) bars an Ordinance from taking away or abridging Fundamental Rights, exactly as it bars a statute. Retrospective operation is an ordinary incident of legislative power, so an Ordinance may be given effect from a back date; the only firm bar is Article 20(1), which forbids retrospective criminal liability or enhanced penalties. Krishna Kumar Singh v. State of Bihar (2017) confirmed that ordinance-making is subject to judicial review and that laying the Ordinance before the legislature is mandatory.

Prepared with PrepKar AI and checked; it may contain errors.

Option (c), both statements are correct. The Nagpur session of December 1920 changed the Congress creed to attaining swaraj by all legitimate and peaceful means, and Gandhi's programme was explicitly staged, holding civil disobedience and tax refusal in reserve. At Nagpur (December 1920, presided over by C. Vijayaraghavachariar) the Congress ratified the Non-Cooperation resolution passed at the Calcutta special session of September 1920 and amended Article I of its constitution: the goal became 'swaraj by all legitimate and peaceful means', dropping the earlier commitment to constitutional methods within the Empire. Gandhi promised 'swaraj within a year' and set out the movement in phases — surrender of titles and honorary offices, boycott of schools, courts, councils and foreign cloth first, with mass civil disobedience and non-payment of taxes only if swaraj did not arrive within the year or the government resorted to repression. Nagpur also restructured the Congress itself: the Working Committee, linguistic Provincial Congress Committees, and a four-anna membership fee that opened it to the masses.

Prepared with PrepKar AI and checked; it may contain errors.

The answer is (d) Neither 1 nor 2. Both statements swap the roles of the two cloud types: it is low, thick clouds that reflect sunlight and cool the surface, while high, thin clouds let sunlight through and trap outgoing infrared, warming the surface. Clouds affect the heat budget in two opposite ways depending on their height and thickness. Low, thick clouds (stratus, nimbostratus) have a high albedo: they reflect a large share of incoming short-wave solar radiation back to space, so their net effect is cooling. High, thin clouds (cirrus, made of ice crystals) are largely transparent to incoming sunlight but absorb the long-wave infrared radiation emitted by the Earth's surface and re-radiate part of it downward, so their net effect is warming. Statement 1 gives high clouds the low-cloud role, and statement 2 gives low clouds the high-cloud role, so both are wrong. This follows from the heat-budget discussion in NCERT Class 11 Fundamentals of Physical Geography, Ch. 9 (Solar Radiation, Heat Balance and Temperature).

Prepared with PrepKar AI and checked; it may contain errors.

(b) Increase in the banking habit of the population. Better banking habits mean people hold less cash and more deposits, which lowers the currency-deposit ratio and raises the money multiplier. The money multiplier is the ratio of money supply to high-powered money (reserve money): m = M/H = (1+cdr)/(cdr+rdr), where cdr is the currency-deposit ratio and rdr the reserve-deposit ratio. Since rdr is less than 1, a fall in cdr raises the multiplier. When banking habits improve, the public keeps a larger share of its money in bank deposits rather than as cash, so cdr falls and each rupee of reserve money supports more deposit creation. Raising CRR or SLR does the opposite by increasing the reserve-deposit ratio, which shrinks the multiplier.

Prepared with PrepKar AI and checked; it may contain errors.

Option (c) — statements 2 and 3 only. Prorogation and dissolution are both presidential acts performed on ministerial advice, so statement 1's claim that prorogation needs no advice is wrong. Article 85(2)(a) lets the President prorogue the Houses, but Article 74(1) binds the President to act on the aid and advice of the Council of Ministers in all such functions — prorogation is not a discretionary power. Prorogation ends a session and usually follows adjournment sine die, yet nothing stops the President from proroguing a House that is still in session, which has happened in practice. Dissolution under Article 85(2)(b) is likewise done on ministerial advice, with a narrow situational discretion recognised only when the government has lost or cannot prove its majority.

Prepared with PrepKar AI and checked; it may contain errors.

Option (d), all three statements are correct. Methane hydrate is methane locked in an ice-like water cage that is stable only under cold, high-pressure conditions, so warming can release it; it occurs in Arctic permafrost and marine sediments; and atmospheric methane oxidises to carbon dioxide within roughly a decade. Methane hydrate (clathrate) is a crystalline solid in which a cage of water molecules traps a methane molecule; it stays solid only where temperature is low and pressure high, chiefly beneath Arctic permafrost and in continental-margin seafloor sediments a few hundred metres down. Warming of permafrost or ocean-bottom waters destabilises the cage and can release methane — the feared 'clathrate gun' positive feedback. In the atmosphere methane is destroyed mainly by reaction with the hydroxyl radical (OH), giving it a lifetime of about 9-12 years, at the end of which it has been oxidised to carbon dioxide and water; that is why methane is far more potent than CO2 over 20 years but much shorter-lived, and why cutting methane brings quick climate returns.

Prepared with PrepKar AI and checked; it may contain errors.

Option (c) — statements 1 and 3 only. Probiotics do include yeasts as well as bacteria and do help break down lactose, but the whole point of them is that the same or similar organisms already live naturally in our gut. Probiotics are live micro-organisms that confer a health benefit when taken in adequate amounts; the common ones are bacteria (Lactobacillus, Bifidobacterium) but the yeast Saccharomyces boulardii is a well-established probiotic too, so statement 1 holds. Statement 2 fails on its second half: probiotic strains are chosen precisely because they resemble the resident gut flora, which is why they can colonise and survive there. Statement 3 is standard biology — lactic acid bacteria carry beta-galactosidase (lactase), which hydrolyses lactose, and probiotic-rich curd/yogurt is routinely used to ease lactose intolerance. NCERT Class 12 Biology, Ch. 10 'Microbes in Human Welfare' covers Lactobacillus converting milk sugar to lactic acid in curd.

Prepared with PrepKar AI and checked; it may contain errors.

The answer is (c): cooking temperature inside a pressure cooker is set by the steam pressure, which depends on the weight of the lid/valve and the area of the vent hole, not on how hot the flame is. Water boils when its saturated vapour pressure equals the pressure above it, so raising the internal pressure raises the boiling point (about 120 °C at roughly 2 atmospheres in a domestic cooker). That internal pressure is fixed mechanically: steam lifts the weight only when pressure times the hole's area exceeds the weight, so pressure equals weight divided by hole area. A hotter flame only makes steam faster, which escapes through the vent; the temperature still plateaus at the boiling point set by the pressure, so statement 2 is wrong.

Prepared with PrepKar AI and checked; it may contain errors.

Option (b) Keibul Lamjao National Park. It is the world's only floating national park, made of phumdis — mats of decomposed floating vegetation — on Loktak Lake in Manipur. Keibul Lamjao lies on the south-eastern rim of Loktak Lake, Manipur, and its terrain is largely phumdi: heterogeneous masses of soil, vegetation and organic matter in various stages of decay that float on the water and thicken enough to bear the weight of a deer. It was notified a sanctuary in 1966 and a national park in 1977, specifically to save the sangai or Manipur brow-antlered deer (Rucervus eldii eldii), which walks on phumdi and is found nowhere else in the wild. Loktak is also a Ramsar site (1990) and was placed on the Montreux Record in 1993. No other Indian national park is a floating swamp of this kind.

Prepared with PrepKar AI and checked; it may contain errors.

Answer (a) — statements I and II only. Capital receipts are defined as receipts that either create a liability or reduce the government's assets; interest received on loans given out is a non-tax revenue receipt and creates no liability at all. The government budget classifies receipts by their effect on the government's balance sheet. Capital receipts either create a liability (borrowings from the RBI, market loans, small savings, external loans) or reduce financial assets (disinvestment of PSU shares, recovery of loans), so statement I is the textbook definition and statement II gives its two standard examples. Interest received on loans the government has advanced to states, PSUs or others is income flowing in; it neither creates an obligation to repay nor runs down an asset, so it is a revenue receipt — specifically a non-tax revenue receipt, alongside dividends and profits from PSUs and fees for services. That makes statement III wrong, and only option (a) excludes it.

Prepared with PrepKar AI and checked; it may contain errors.

Statements 1 and 2 are correct, 3 is wrong (option a). Wood's Despatch of 1854 introduced grants-in-aid and recommended universities, but it wanted English only for higher education and the vernaculars at the school level. Sir Charles Wood, President of the Board of Control, sent the Despatch of 1854, called the 'Magna Carta of English education in India'. It asked the Company to take responsibility for mass education (rejecting the downward-filtration idea), set up a Department of Public Instruction in each province, and proposed a graded system: vernacular primary schools, Anglo-vernacular high schools, affiliated colleges, and universities in the Presidency towns modelled on London University; Calcutta, Bombay and Madras universities followed in 1857. It introduced a system of grants-in-aid to encourage private schools, and stressed female education, vocational training and teacher training. On language it was explicit: English as the medium for higher studies, Indian languages for school-level teaching. Statement 3 claims English 'at all levels', which contradicts the Despatch.

Prepared with PrepKar AI and checked; it may contain errors.

Only statement 2 is correct, so the answer is (b). Both bodies are statutory — the CPCB was created by the Water Act, 1974, not by an executive order — but their functions do differ as described. The National Green Tribunal was set up by the National Green Tribunal Act, 2010, giving it jurisdiction over civil cases involving a substantial question relating to the environment under seven scheduled laws, with disposal aimed at six months and appeals lying to the Supreme Court. The Central Pollution Control Board was constituted in September 1974 under the Water (Prevention and Control of Pollution) Act, 1974, and later given functions under the Air (Prevention and Control of Pollution) Act, 1981 — so it too is a statutory body, which makes statement 1 wrong. Statement 2 correctly captures the division of labour: the NGT is an adjudicatory forum that delivers speedy environmental justice and takes load off the High Courts and Supreme Court, while the CPCB is a regulatory and technical body that promotes cleanliness of streams and wells and works to improve air quality, setting standards and monitoring compliance.

Prepared with PrepKar AI and checked; it may contain errors.

Answer (b): statements 2 and 3 are correct. An RTG is not a reactor at all — it has no fission chain reaction, only passive radioactive decay feeding a thermocouple. A radioisotope thermoelectric generator converts the heat of natural radioactive decay — usually of plutonium-238 dioxide — directly into electricity using thermocouples exploiting the Seebeck effect across a hot-to-cold temperature gradient. There is no chain reaction, no criticality, no control rods and no moving parts, so calling it a miniature fission reactor is wrong in principle. Because RTGs run for decades without sunlight, they power deep-space and outer-planet missions — Voyager, Cassini, New Horizons, and the Curiosity and Perseverance rovers. Pu-238 is not found in nature; it is made by irradiating neptunium-237, which is itself recovered from reactor fuel and from the plutonium-production infrastructure built for weapons programmes, which is the sense in which statement 3's 'by-product of weapons development' holds.

Prepared with PrepKar AI and checked; it may contain errors.

Option (b): only pair 2 is correct. Nanda Devi is the highest peak of the Kumaon Himalaya; Namcha Barwa is the eastern end of the Himalaya in Tibet, and Nokrek is in the Garo Hills of Meghalaya, not the Himalaya at all. In the classical regional division (Sir Sidney Burrard), the Kumaon Himalaya stretches between the Sutlej and the Kali rivers and its highest peak is Nanda Devi (7,816 m, Chamoli district, Uttarakhand), the highest summit lying entirely within India; NCERT Class 11 groups this as the Himachal and Uttarakhand Himalaya. Namcha Barwa (7,782 m) is the peak around which the Brahmaputra (Yarlung Tsangpo) makes its great bend in Tibet and marks the eastern extremity of the Himalaya, far from Garhwal in western Uttarakhand. Nokrek (1,412 m) is the highest point of the Garo Hills on the Meghalaya plateau, a block of the Peninsular shield, so it cannot belong to the Sikkim Himalaya, whose highest peak is Kangchenjunga.

Prepared with PrepKar AI and checked; it may contain errors.

(a) 23 minutes. With A shuttling every time, all four are across in 21 minutes, and the extra rule — the lamp goes back and its carrier crosses again — adds two more 1-minute trips by A. First read the added rule carefully: the person who returns must be the faster member of the pair that has just crossed. That switches off the memorised shortcut of sending the two slowest together, because if C and D crossed as a pair, C would have to walk back and cost 7 minutes. So A, the fastest, becomes the permanent ferry. Step 1: A and B cross together — a pair moves at the slower person's speed, so 2 minutes. A returns with the lamp, 1 minute. Running total 3; B is across. Step 2: A and C cross, 7 minutes; A returns, 1 minute. Running total 11; B and C are across. Step 3: A and D cross, 10 minutes. Running total 21; all four are now across. Step 4: the lamp is still on the far side, so A carries it back, 1 minute (total 22), leaves it at the original place, and crosses again without it, 1 minute (total 23). The order of the middle pairings does not matter — A with D first and B last also gives 10 + 1 + 7 + 1 + 2 = 21. Sending C and D together instead pushes the crossings to 27 minutes, so 21 + 2 = 23 is the minimum.

Prepared with PrepKar AI and checked; it may contain errors.

Option (a): only statement 1 is correct. India is a member of the International Grains Council, but IGC membership is in no way a licence or precondition for trading rice and wheat. The International Grains Council is an intergovernmental body operating under the Grains Trade Convention 1995, successor to the International Wheat Council of 1949; India is a member. Its functions are cooperative and informational — market analysis, price indices, consultations among exporting and importing members — not regulatory. Grain trade is governed by national policy and by WTO agreements (notably the Agreement on Agriculture), so any country, member or not, can export or import rice and wheat. Statement 2 confuses a consultative forum with a trading permit.

Prepared with PrepKar AI and checked; it may contain errors.

Only statements 2 and 3 are correct, so the answer is (b). The stupa form is pre-Buddhist — it appears in Vedic literature as a mound or heap — even though Buddhism made it a relic shrine and an object of veneration. The word stupa simply means a heap or mound and occurs in the Rigveda and later Vedic texts; funerary mounds over the ashes of the dead existed in India before the Buddha, so the concept is not Buddhist in origin — Buddhism adopted and elaborated it. In Buddhist practice the stupa was built over corporeal relics (sharirika), objects used by the Buddha (paribhogika), or at sites linked to his life, and the Mahaparinibbana Sutta records the division of the Buddha's relics among eight claimants. Stupas were also raised as votive offerings by pilgrims and donors and as commemorative markers — Sanchi and Bharhut are ringed by small votive stupas with donor inscriptions. Hence statement 1 is wrong while 2 and 3 stand.

Prepared with PrepKar AI and checked; it may contain errors.

The answer is (a) 110. There are 100 numbers beginning with 2 and 20 ending with 2, and 10 numbers do both, so the count is 100 + 20 minus 10 = 110. Every number between 100 and 300 has three digits, so beginning with 2 means the hundreds digit is 2, and ending with 2 means the units digit is 2. Count the first group: 200 to 299, which is 299 minus 200 plus 1 = 100 numbers. Count the second group: 102, 112, 122 and so on up to 292, rising in steps of 10, which is (292 minus 102) divided by 10, plus 1, that is 19 plus 1 = 20 numbers. The two groups overlap, because 202, 212 and so on up to 292 both begin and end with 2; that overlap is (292 minus 202) divided by 10, plus 1, which is 10 numbers. Simply adding 100 and 20 counts those 10 numbers twice, so subtract them once: 100 + 20 minus 10 = 110. The shortcut is to avoid the double count altogether by splitting into groups that cannot overlap: take all 100 numbers from 200 to 299, then add only the numbers ending in 2 that lie below 200, namely 102 up to 192, which is 10 numbers, giving 110 directly. That version needs one subtraction fewer and takes about twenty seconds, while listing the numbers out by hand would cost two or three minutes. The endpoints change nothing, since neither 100 nor 300 begins or ends with 2.

Prepared with PrepKar AI and checked; it may contain errors.