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BPSC Headmaster practice questions

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Question 1General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Permanent Settlement of 1793 was introduced by Lord Cornwallis primarily in which region of British India?

  1. Bombay Presidency
  2. Punjab and Sindh
  3. Madras Presidency
  4. Bengal and Bihar Correct answer.

Explanation

The Permanent Settlement (Zamindari System) was implemented in 1793 in Bengal and Bihar, later extended to parts of Orissa and Varanasi. Under it, zamindars were recognised as hereditary owners who paid a fixed revenue to the Company. Madras and Bombay were largely covered by the Ryotwari system instead.

Question 2General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which Article of the Constitution of India provides for the establishment of a Finance Commission by the President every fifth year or earlier?

  1. Article 356
  2. Article 324
  3. Article 280 Correct answer.
  4. Article 263

Explanation

Article 280 mandates that the President constitute a Finance Commission within two years of the commencement of the Constitution and thereafter at the expiry of every fifth year or earlier. Its core function is to recommend distribution of net tax proceeds between the Union and the States and the principles governing grants-in-aid.

Question 3General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Tropic of Cancer passes through which of the following Indian States?

  1. Kerala
  2. Tamil Nadu
  3. Karnataka
  4. Rajasthan Correct answer.

Explanation

The Tropic of Cancer at roughly 23.5 degrees north latitude passes through eight Indian States, including Rajasthan, Gujarat, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura and Mizoram. Kerala, Tamil Nadu and Karnataka lie entirely south of this line.

Question 4General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which body decides the repo rate in India's monetary policy framework?

  1. Finance Commission
  2. Monetary Policy Committee Correct answer.
  3. Union Cabinet
  4. Securities and Exchange Board of India

Explanation

Since the 2016 amendment to the RBI Act, the six-member Monetary Policy Committee determines the policy repo rate to achieve the inflation target. It has three RBI members and three external members, with the RBI Governor casting a deciding vote in a tie.

Question 5General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Battle of Plassey in 1757 was fought between the forces of the English East India Company and which ruler?

  1. Shah Alam II
  2. Tipu Sultan
  3. Siraj-ud-Daulah Correct answer.
  4. Mir Qasim

Explanation

At Plassey, Robert Clive defeated Nawab Siraj-ud-Daulah of Bengal with the help of Mir Jafar's defection. The victory gave the Company effective political control over Bengal's revenues. Mir Qasim was installed as Nawab later, and Tipu Sultan ruled Mysore.

Question 6General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which schedule of the Constitution of India contains the list of recognised languages?

  1. Tenth Schedule
  2. Ninth Schedule
  3. Seventh Schedule
  4. Eighth Schedule Correct answer.

Explanation

The Eighth Schedule lists the languages recognised by the Constitution, originally fourteen and now twenty-two after amendments adding Sindhi, Konkani, Manipuri, Nepali and Bodo. It is distinct from the Seventh Schedule, which divides legislative powers.

Question 7General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Green Revolution in India during the late 1960s was most closely associated with which crop?

  1. Tea
  2. Wheat Correct answer.
  3. Jute
  4. Cotton

Explanation

The Green Revolution introduced high-yielding dwarf varieties of wheat, notably developed with Norman Borlaug's research, along with assured irrigation and fertilisers. Punjab, Haryana and western Uttar Pradesh recorded the sharpest gains in wheat output.

Question 8General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which State of India has the longest coastline?

  1. Andhra Pradesh
  2. Tamil Nadu
  3. Gujarat Correct answer.
  4. Maharashtra

Explanation

Gujarat has the longest coastline among Indian States, at roughly 1,600 km, owing to the deeply indented Gulf of Kachchh and Gulf of Khambhat. Its numerous creeks and inlets account for this length.

Question 9General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Who was the founder of the Slave Dynasty in India?

  1. Balban
  2. Qutb-ud-din Aibak Correct answer.
  3. Iltutmish
  4. Razia Sultan

Explanation

Qutb-ud-din Aibak founded the Slave or Mamluk Dynasty after Muhammad Ghori's death in 1206, ruling from Lahore and later Delhi. He began construction of the Qutb Minar, which Iltutmish completed.

Question 10General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which writ is issued by a court to a public authority to compel it to perform a duty that it has failed to discharge?

  1. Quo Warranto
  2. Certiorari
  3. Mandamus Correct answer.
  4. Habeas Corpus

Explanation

Mandamus literally means 'we command' and directs a public authority to perform a legal duty it has refused or neglected. It cannot be issued against a private individual or against the President or Governors in their discretion.

Question 11General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Godavari river, often called the Dakshin Ganga, originates in which State?

  1. Madhya Pradesh
  2. Karnataka
  3. Maharashtra Correct answer.
  4. Telangana

Explanation

The Godavari rises at Trimbakeshwar in the Nashik district of Maharashtra and flows east across the Deccan into the Bay of Bengal. It is the second longest river in India after the Ganga and drains parts of Maharashtra, Telangana, Andhra Pradesh, Chhattisgarh and Odisha.

Question 12General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Indian Councils Act of 1909, associated with Morley and Minto, is best remembered for introducing which feature?

  1. A federal court
  2. Provincial autonomy
  3. Dyarchy in the provinces
  4. Separate electorates for Muslims Correct answer.

Explanation

The Morley-Minto Reforms of 1909 legalised separate electorates for Muslims, a step that institutionalised communal representation in Indian politics. They also enlarged the legislative councils. Dyarchy and provincial autonomy came with the Acts of 1919 and 1935 respectively.

Question 13General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following is a direct tax in India?

  1. Goods and Services Tax
  2. Income tax Correct answer.
  3. Excise duty on petroleum products
  4. Customs duty

Explanation

A direct tax is levied on income or wealth and its burden cannot be shifted to another person; income tax is the standard example. Indirect taxes such as GST, customs and excise are passed on to the consumer through prices.

Question 14General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Preamble to the Constitution of India was amended by which amendment, adding the words 'Socialist', 'Secular' and 'Integrity'?

  1. 73rd Amendment
  2. 52nd Amendment
  3. 42nd Amendment Correct answer.
  4. 44th Amendment

Explanation

The 42nd Amendment Act of 1976, enacted during the Emergency, inserted the words 'Socialist' and 'Secular' into the Preamble and replaced 'unity of the Nation' with 'unity and integrity of the Nation'. It is often called the mini-Constitution for its wide sweep.

Question 15General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following soils is formed by the deposition of material brought by rivers and is most widespread in the northern plains of India?

  1. Laterite soil
  2. Red soil
  3. Black soil
  4. Alluvial soil Correct answer.

Explanation

Alluvial soil is transported and deposited by rivers and covers the Indo-Gangetic plains and coastal deltas; it is the most extensive soil group in India. Black soil derives from lava and suits cotton, while laterite forms in hot, wet conditions through leaching.

Question 16General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Civil Disobedience Movement was launched by Mahatma Gandhi in 1930 with which specific action?

  1. The Quit India resolution
  2. The launch of the Swadeshi boycott of foreign cloth
  3. The Dandi March to make salt Correct answer.
  4. The Champaran satyagraha

Explanation

Gandhi began the Civil Disobedience Movement with the Dandi March in March-April 1930, walking about 240 miles to the sea to break the salt law. Salt was chosen because it was a monopoly tax affecting every household, making it a symbol of colonial exploitation.

Question 17General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

In the context of Indian federalism, which of the following subjects falls in the Concurrent List?

  1. Defence
  2. Police
  3. Currency
  4. Education Correct answer.

Explanation

Education was moved to the Concurrent List by the 42nd Amendment in 1976, allowing both Parliament and State legislatures to legislate on it. Defence, currency and police remain respectively in the Union List and State List.

Question 18General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following is the largest source of tax revenue for the Union Government in recent years?

  1. Union excise duty
  2. Goods and Services Tax Correct answer.
  3. Customs duty
  4. Corporation tax

Explanation

After the 2017 roll-out of GST, the Goods and Services Tax has grown to become the single largest indirect tax contributor to the Union's gross tax revenue, alongside corporation tax as the largest direct tax head. GST subsumed many earlier indirect taxes, which shrank excise and customs collections.

Question 19General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The 'Doctrine of Lapse' used by Lord Dalhousie was applied to annex which of the following States?

  1. Awadh
  2. Sindh
  3. Satara Correct answer.
  4. Punjab

Explanation

The Doctrine of Lapse denied adoption rights to rulers without natural heirs, allowing the Company to annex dependent States; Satara was annexed on this basis in 1848. Punjab and Sindh were taken by conquest, and Awadh was annexed in 1856 on grounds of misgovernment.

Question 20General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following is the correct order of the Himalayan ranges from south to north?

  1. Lesser Himalaya, Shiwalik, Great Himalaya
  2. Great Himalaya, Lesser Himalaya, Shiwalik
  3. Shiwalik, Lesser Himalaya, Great Himalaya Correct answer.
  4. Shiwalik, Great Himalaya, Lesser Himalaya

Explanation

Moving north from the plains, the Shiwalik foothills come first, then the Lesser or Middle Himalaya with ranges such as Pir Panjal and Dhauladhar, and finally the Great Himalaya with the highest peaks. The Shiwaliks are the youngest and most southerly of the three.

Question 21General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Panchayati Raj institutions were given constitutional status by which amendment?

  1. 73rd Amendment Correct answer.
  2. 74th Amendment
  3. 86th Amendment
  4. 61st Amendment

Explanation

The 73rd Amendment Act of 1992 inserted Part IX and the Eleventh Schedule, giving constitutional status to rural local bodies and mandating three-tier Panchayati Raj. It also provided for reservation and a five-year term.

Question 22General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Consider a State where the Governor reserves a bill for the consideration of the President. Under the Constitution, the President may do which of the following?

  1. Return the bill directly to the State legislature without consulting the Governor
  2. Only withhold assent
  3. Give assent, withhold assent, or direct the Governor to return the bill to the State legislature Correct answer.
  4. Only give assent

Explanation

Under Article 201, when a bill is reserved for the President's consideration, the President may assent, withhold assent, or direct the Governor to return the bill to the House for reconsideration. If the House passes it again, the President is not bound to give assent.

Question 23General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following best explains why the Ryotwari system produced different revenue outcomes from the Permanent Settlement?

  1. Revenue was settled directly with cultivators and periodically revised, so the State could capture gains from rising output Correct answer.
  2. The village community collectively paid a lump sum to the State
  3. Revenue was collected entirely in kind rather than cash
  4. Zamindars were made permanent owners with a fixed demand in perpetuity

Explanation

In the Ryotwari areas of Madras and Bombay, the State dealt directly with the individual ryot and revised the demand periodically, usually after a survey, so increases in output could be tapped. In the Permanent Settlement, the fixed demand benefited the zamindar if rents rose, while the State's share stagnated.

Question 24General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

A State's share in the divisible pool of central taxes has been rising across successive Finance Commissions. Which factor most directly explains this trend?

  1. A constitutional amendment raising the States' share to a fixed 50 per cent
  2. The transfer of Union List subjects to the State List
  3. A larger weight assigned to the income distance criterion relative to previous practice Correct answer.
  4. The abolition of cesses and surcharges by Parliament

Explanation

Successive Finance Commissions, notably the 14th and 15th, raised the States' share largely by increasing the weight given to income distance, which favours poorer States, while reducing the weight of less progressive criteria. The share is recommended, not fixed by a constitutional amendment, and cesses and surcharges remain outside the divisible pool.

Question 25General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following statements about the Western and Eastern Ghats is correct?

  1. The Eastern Ghats are higher and more continuous than the Western Ghats
  2. Both ranges are of equal height and continuity
  3. The Western Ghats are higher and more continuous, while the Eastern Ghats are lower and dissected by rivers Correct answer.
  4. The Eastern Ghats receive heavier orographic rainfall than the Western Ghats

Explanation

The Western Ghats form a relatively continuous escarpment with average heights of 900 to 1,600 metres and intercept the south-west monsoon, producing heavy rain. The Eastern Ghats are lower, discontinuous and cut by rivers such as the Mahanadi, Godavari and Krishna as they reach the coast.

Question 26General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which Article of the Constitution of India provides for the establishment of an All India Services?

  1. Article 315
  2. Article 324
  3. Article 312 Correct answer.
  4. Article 280

Explanation

Article 312 empowers Parliament to create new All India Services common to the Union and the States, provided a Rajya Sabha resolution supports it by a special majority. The Indian Administrative Service and Indian Police Service already existed, while later services such as the Indian Forest Service were created under this Article.

Question 27General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Battle of Buxar in 1764 was fought between the British East India Company and a combined force of which rulers?

  1. Mir Qasim, Shuja-ud-Daula and Shah Alam II Correct answer.
  2. Tipu Sultan and the Nizam of Hyderabad
  3. Siraj-ud-Daula and the French under Dupleix
  4. Hyder Ali and the Maratha confederacy

Explanation

At Buxar the Company force under Hector Munro defeated the triple alliance of Mir Qasim of Bengal, Shuja-ud-Daula of Awadh and the Mughal emperor Shah Alam II. The victory was more decisive than Plassey and led to the Treaty of Allahabad in 1765 granting the Company the Diwani of Bengal, Bihar and Orissa.

Question 28General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following is the chief characteristic of the black cotton soil of the Deccan region?

  1. High moisture retention and self-ploughing on drying Correct answer.
  2. High nitrogen content and low clay fraction
  3. Coarse sandy texture with rapid drainage
  4. Strongly acidic reaction with high organic matter

Explanation

Black soil, formed from lava basalt, is rich in clay minerals that hold moisture strongly and swell when wet. On drying it contracts and develops deep cracks that turn the soil over, which is why it is called self-ploughing. It is also poor in nitrogen and phosphorus but rich in iron, lime and magnesia.

Question 29General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

In the context of Indian public finance, which of the following is the best example of a 'public good' justifying government provision?

  1. Packaged drinking water
  2. Air travel between metros
  3. National defence Correct answer.
  4. Mobile telephone service

Explanation

A public good is non-rival and non-excludable, so the market underprovides it and government financing is needed. National defence meets both conditions because protecting one citizen does not reduce protection of others and non-payers cannot be excluded. The other items are rival and excludable and are efficiently supplied through markets.

Question 30General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which session of the Indian National Congress adopted the resolution on 'Purna Swaraj' as its goal?

  1. Calcutta session of 1928
  2. Karachi session of 1931
  3. Lahore session of 1929 Correct answer.
  4. Nagpur session of 1920

Explanation

At the Lahore session of December 1929, presided over by Jawaharlal Nehru, the Congress declared complete independence as its goal and authorised the observance of 26 January 1930 as Independence Day. The flag was hoisted on the banks of the Ravi during that session.

Question 31General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

The Tropic of Cancer passes through which of the following States of India?

  1. Karnataka
  2. Kerala
  3. Andhra Pradesh
  4. Madhya Pradesh Correct answer.

Explanation

The Tropic of Cancer crosses eight Indian States, and Madhya Pradesh is one of them, passing near Bhopal. The other listed States lie entirely south of the line. The eight States are Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura and Mizoram.

Question 32General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following best explains why the Government of India Act of 1935 is regarded as a major source of the Indian Constitution?

  1. It established the Supreme Court of India as the final court of appeal
  2. It supplied much of the federal scheme, Governor's powers and emergency provisions Correct answer.
  3. It granted universal adult franchise and a bill of rights
  4. It abolished the office of the Governor-General

Explanation

The Act of 1935 created a federation with divided powers, provincial autonomy and special responsibilities for Governors, and its emergency and administrative machinery was largely retained by the framers. The Constitution's federal list, provincial list and much of the emergency framework are drawn from it. It did not, however, provide a bill of rights or universal adult franchise.

Question 33General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following is the correct meaning of 'Repo Rate' in Indian monetary policy?

  1. The rate at which the RBI absorbs liquidity from the banking system
  2. The rate at which banks lend to their most creditworthy customers
  3. The rate of interest paid by the government on small savings schemes
  4. The rate at which the RBI lends short-term funds to banks against government securities Correct answer.

Explanation

The repo rate is the policy rate at which the Reserve Bank lends overnight or short-term funds to commercial banks against eligible collateral such as government securities. Raising it makes credit costlier and helps control inflation, while lowering it stimulates borrowing. The reverse operation, absorbing liquidity, is the reverse repo.

Question 34General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following statements about the office of the Chief Minister of a State is correct?

  1. The Chief Minister is appointed by the Governor and must command a majority in the Legislative Assembly Correct answer.
  2. The Chief Minister must be a member of the Legislative Council
  3. The Chief Minister is directly elected by the people of the State in a separate election
  4. The Chief Minister is appointed by the President on the advice of the Prime Minister

Explanation

Under Article 164 the Governor appoints the Chief Minister, and the Council of Ministers is collectively responsible to the Legislative Assembly. In practice the Governor must invite the leader who can command a majority in the Assembly. A person who is not a member of either House may be appointed but must secure membership within six months.

Question 35General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Consider a State whose Legislative Assembly passes a bill on a subject in the Concurrent List that conflicts with an earlier Union law on the same subject. Which condition allows the State law to prevail?

  1. If the State law received the President's assent and was reserved for his consideration Correct answer.
  2. If the State law was passed after the Union law was published
  3. If the Governor certified that the law is of local importance
  4. If the State law was passed by a two-thirds majority of the Assembly

Explanation

Under Article 254, a State law on a Concurrent subject that conflicts with Union law is void to the extent of repugnancy unless it has been reserved for and received the President's assent. Even then, Parliament can subsequently override it by legislating again on the same matter. Mere later enactment does not displace the Union law.

Question 36General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following pairs of an Indian river and its tributary is correctly matched?

  1. Mahanadi - Beas
  2. Ganga - Godavari
  3. Krishna - Tungabhadra Correct answer.
  4. Narmada - Son

Explanation

The Tungabhadra is a major tributary of the Krishna, formed by the union of the Tunga and Bhadra rivers and joined later by the Bhima and Koyna. The Son joins the Ganga, and the Beas belongs to the Indus system, so the other pairings are geographically impossible.

Question 37General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following was the main purpose of the Rowlatt Act of 1919?

  1. To allow detention without trial for suspected revolutionary activity Correct answer.
  2. To establish provincial autonomy in the States
  3. To transfer the capital of India from Calcutta to Delhi
  4. To introduce separate electorates for religious communities

Explanation

The Rowlatt Act empowered the government to arrest and detain persons suspected of sedition without trial and to try such cases without a jury. The widespread protest against it, culminating in the Jallianwala Bagh massacre, marked a turning point in Gandhi's move towards mass agitation.

Question 38General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following is the correct sequence of the stages of the Indian budgeting process?

  1. Presentation of the Budget, discussion and voting on demands, appropriation bill, finance bill Correct answer.
  2. Discussion on demands, finance bill, Budget presentation, appropriation bill
  3. Appropriation bill, Budget presentation, finance bill, discussion on demands
  4. Finance bill, appropriation bill, Budget presentation, discussion on demands

Explanation

The Annual Financial Statement is first presented in Parliament, then general discussion takes place, followed by voting on demands for grants. The Appropriation Bill authorises withdrawal from the Consolidated Fund, and the Finance Bill gives effect to the taxation proposals.

Question 39General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following States of India shares the longest border with Nepal?

  1. West Bengal
  2. Sikkim
  3. Uttar Pradesh Correct answer.
  4. Bihar

Explanation

Uttar Pradesh has the longest boundary with Nepal among Indian States, running for roughly 560 kilometres along districts such as Maharajganj, Siddharthnagar and Bahraich. Bihar, Sikkim, West Bengal and Uttarakhand also border Nepal but with shorter stretches.

Question 40General Studies (Indian History, Polity, Geography, Economy, and Current Affairs)

Which of the following describes the 'Gandhi-Irwin Pact' of 1931?

  1. The Congress agreed to accept dominion status within a year
  2. The Congress agreed to suspend civil disobedience and attend the Second Round Table Conference Correct answer.
  3. The Congress agreed to drop the demand for complete independence permanently
  4. The Congress agreed to boycott the Round Table Conference in exchange for release of prisoners

Explanation

Under the pact signed in March 1931, Gandhi agreed to call off the Civil Disobedience Movement and join the Second Round Table Conference, while the government released political prisoners and withdrew some repressive ordinances. The Congress did not abandon the goal of complete independence.

Question 41General Science and Environmental Awareness

Which gas makes up the largest share of Earth's atmosphere by volume?

  1. Nitrogen Correct answer.
  2. Argon
  3. Carbon dioxide
  4. Oxygen

Explanation

Dry air is roughly 78 per cent nitrogen and 21 per cent oxygen, so nitrogen clearly dominates. Carbon dioxide is only about 0.04 per cent and argon under 1 per cent, so neither can be the largest component.

Question 42General Science and Environmental Awareness

A headmaster wants to demonstrate that light travels in straight lines. Which classroom observation best supports this?

  1. A pencil appears bent when partly dipped in a glass of water
  2. A shadow forms behind an opaque object placed in the path of a torch beam Correct answer.
  3. A prism splits white light into a band of colours
  4. A mirror reverses left and right in the image it forms

Explanation

Rectilinear propagation means light travels in straight lines in a uniform medium, so an opaque object blocks it and leaves a sharp shadow. Prism dispersion, refraction in water and image formation in mirrors involve other phenomena and do not by themselves demonstrate straight-line travel.

Question 43General Science and Environmental Awareness

Which part of a flowering plant is the main site of photosynthesis?

  1. Leaf mesophyll Correct answer.
  2. Root hair
  3. Anther
  4. Petal

Explanation

Photosynthesis needs chlorophyll and light, and the palisade and spongy mesophyll cells of the leaf are packed with chloroplasts. Roots, petals and anthers contain little or no chlorophyll and are not the principal photosynthetic tissue.

Question 44General Science and Environmental Awareness

Which of the following is a renewable source of energy?

  1. Petroleum
  2. Natural gas
  3. Coal
  4. Wind Correct answer.

Explanation

Renewable sources are replenished naturally on a human timescale, and wind is driven by solar heating of the atmosphere. Coal, petroleum and natural gas are fossil fuels formed over millions of years and are consumed far faster than they form.

Question 45General Science and Environmental Awareness

Which vitamin deficiency in children is classically associated with night blindness?

  1. Vitamin C
  2. Vitamin A Correct answer.
  3. Vitamin K
  4. Vitamin D

Explanation

Vitamin A is needed to make rhodopsin, the light-sensitive pigment of the rod cells, so deficiency impairs vision in dim light. Vitamin C deficiency causes scurvy, vitamin D deficiency causes rickets, and vitamin K deficiency impairs clotting.

Question 46General Science and Environmental Awareness

Which of the following is a biotic component of a pond ecosystem?

  1. Water temperature
  2. Aquatic weeds Correct answer.
  3. Dissolved oxygen
  4. Humus in the bottom mud

Explanation

Biotic components are the living organisms of an ecosystem, and aquatic weeds are producers. Dissolved oxygen, temperature and humus are abiotic physical or chemical factors of the habitat.

Question 47General Science and Environmental Awareness

A school conducts a plantation drive and wants to reduce airborne particulate matter in its playground. Which measure is most directly effective?

  1. Replacing chalkboards with whiteboards inside classrooms
  2. Planting a dense belt of trees and shrubs along the boundary Correct answer.
  3. Painting the school walls with a lighter colour
  4. Increasing the number of drinking-water taps

Explanation

Tree and shrub belts intercept dust particles on leaf surfaces and slow wind speed, allowing particulates to settle. Wall colour, indoor board type and water taps do not remove suspended particles from outdoor air.

Question 48General Science and Environmental Awareness

Which of the following best explains why the sky appears blue during the day?

  1. Air molecules emit blue light after absorbing sunlight
  2. The ozone layer reflects blue light back to the ground
  3. Short wavelengths of sunlight are scattered more strongly by air molecules Correct answer.
  4. Water vapour in the air absorbs all colours except blue

Explanation

Rayleigh scattering is inversely proportional to the fourth power of wavelength, so blue light is scattered far more than red. This scattered blue light reaches the observer from all directions, giving the sky its colour.

Question 49General Science and Environmental Awareness

A body moves along a straight line with constant acceleration and starts from rest. If it covers 45 m in the first 3 s, what is its acceleration?

  1. 5 m/s²
  2. 10 m/s² Correct answer.
  3. 15 m/s²
  4. 30 m/s²

Explanation

Using s = ut + ½at² with u = 0 gives 45 = ½ × a × 9, so a = 10 m/s². Substituting any other option into the same equation fails to give 45 m in 3 s.

Question 50General Science and Environmental Awareness

Which blood vessel carries oxygenated blood from the lungs to the heart?

  1. Pulmonary artery
  2. Pulmonary vein Correct answer.
  3. Aorta
  4. Vena cava

Explanation

The pulmonary veins return oxygenated blood from the lungs to the left atrium, which is the exception to the rule that veins carry deoxygenated blood. The pulmonary artery carries deoxygenated blood to the lungs, while the vena cava and aorta serve the systemic circuit.