The name of the BrahMos missile is derived from the names of which two rivers?

The correct answer is B, 1983. The Integrated Guided Missile Development Programme, usually written IGMDP, was approved in 1983 and placed under the Defence Research and Development Organisation, with A. P. J. Abdul Kalam as its head. Its aim was to build five missiles together rather than one after another, and the programme was formally declared complete in 2008.

Option A, 1974, is the year of Pokhran-I, the peaceful nuclear explosion codenamed Smiling Buddha, which candidates often bring here. Option C, 1991, is remembered for economic liberalisation, not for missiles. Option D, 1998, is the year of Pokhran-II, the series of nuclear tests at Pokhran under Operation Shakti, and it is the commonest wrong choice because the same period saw Agni tests. Only 1983 belongs to the IGMDP.

The correct answer is C, BrahMos. The five missiles of the IGMDP were Prithvi, Agni, Trishul, Akash and Nag. BrahMos came later and from a different route altogether, as a joint venture between India and Russia, and it is a supersonic cruise missile, while the IGMDP produced ballistic and guided missiles of Indian design.

Option A, Trishul, was the short-range surface-to-air missile of the programme, and the project was later closed. Option B, Nag, is the third generation fire and forget anti-tank guided missile of the programme, carried on the NAMICA vehicle. Option D, Akash, is the medium-range surface-to-air missile with a ramjet engine that is now in service with the Army and the Air Force. All three belong to the original five, so BrahMos is the odd one out.

The correct answer is B, anti-tank guided missile. Nag is a third generation anti-tank guided missile of the fire and forget kind, which means the operator can leave cover once the missile has locked on to the target. It is carried on a tracked vehicle called the NAMICA, short for Nag Missile Carrier, and its helicopter-launched versions are known as Helina and Dhruvastra.

Option A describes Akash, Trishul and the Quick Reaction Surface-to-Air Missile, which engage aircraft. Option C describes Astra, India's beyond-visual-range air-to-air missile carried by the Su-30MKI and the Tejas. Option D describes the Agni-V class, with a range beyond five thousand kilometres. All four categories exist in the Indian inventory, so the question tests whether the name has been tied to the right role.

The correct answer is A, medium-range surface-to-air missile. Akash was one of the five missiles of the IGMDP and is meant to destroy aircraft and helicopters at medium range. It is notable for using a ramjet engine, which lets it keep thrust through the flight, and it works with the Rajendra phased array radar. Both the Army and the Air Force use it, and an export version has been cleared by the government.

Option B describes the K series, the K-15 or Sagarika and the K-4, built for the Arihant class of submarines. Option C describes Rudram, the air-launched missile that homes in on enemy radars. Option D describes Nirbhay, the long-range cruise missile powered by a turbofan engine. Each is a real Indian system, so the answer turns on the role of Akash as an air defence missile.

The correct answer is B, beyond-visual-range air-to-air. Astra is fired from a fighter aircraft at another aircraft that is still beyond the pilot's sight, which is what beyond visual range means, and it uses an active radar seeker in its final phase. It is integrated on the Su-30MKI and on the Tejas light combat aircraft, and it replaces imported missiles of the same class.

Option A, surface-to-surface, describes Prithvi, Agni, Prahaar and Pralay. Option C, anti-tank, describes Nag with its NAMICA carrier and its helicopter versions Helina and Dhruvastra. Option D, anti-ship, describes the naval role of BrahMos and of the Sea Eagle class of weapons. The word Astra, meaning a weapon that is thrown, is easy to confuse with the others, so fix it in memory as the air-to-air missile.