Answer: A

Explanation:

Components of a nuclear power plant

Fuel: Uranium is the basic fuel. Usually pellets of uranium oxide (UO2) are arranged in tubes to form fuel rods. The rods are arranged into fuel assemblies in the reactor core. In a 1000 MWe class PWR there might be 51,000 fuel rods with over 18 million pellets. Hence, pair 1 is not correctly matched.

Moderator: Material in the core which slows down the neutrons released from fission so that they cause more fission. It is usually water, but may be heavy water or graphite. Hence, pair 2 is not correctly matched.

Control rods or blades: These are made with neutron-absorbing material such as cadmium, hafnium or boron, and are inserted or withdrawn from the core to control the rate of reaction, or to halt it. Hence, pair 3 is not correctly matched.

Coolant: A fluid circulating through the core so as to transfer the heat from it. In light water reactors the water moderator functions also as primary coolant. Hence, pair 4 is correctly matched.

Answer: B

Explanation:

India embarked on the path of nuclear weapons development after its face-off with China in the 1962 war, followed by China carrying out nuclear tests in 1964 and in the subsequent years. In 1974, under Prime Minister Indira Gandhi, India conducted its first nuclear tests, Pokhran-I, dubbed as a “peaceful nuclear explosion”. Hence, statement 1 is incorrect.

Despite more than two decades of international pressure that followed to make India abandon its pursuit of nuclear weapons, India again carried out a test in May 1998, Pokhran-II, involving a fission device, a low-yield device, and a thermonuclear device. Its successful execution meant that India had the ability to introduce nuclear warheads into its fast-developing missile programme. Hence, statement 2 is correct.

Answer: C

Explanation:

According to the Atomic Minerals Directorate for Exploration and Research (AMD), a constituent Unit of the Department of Atomic Energy (DAE), India has 11.93 million tonnes of Monazite (ore) which contains about 1.07 million tonnes of thorium. The country’s thorium reserves make up 25 per cent of the global reserves. It can easily be used as a fuel to cut down on the import of Uranium from different countries. Hence, statement 1 is correct.

Through U-233 that could be produced from it releases 8 times the amount of energy per unit mass compared to natural Uranium. In waste generation also, it has a relative advantage over Uranium. Thorium dioxide is much more stable the Uranium dioxide. Hence, statement 2 is correct.

Answer: C

Explanation:

The International Atomic Energy Agency is an international organization that seeks to promote the peaceful use of nuclear energy and inhibit its use for any military purpose, including nuclear weapons. Hence, statement 1 is correct.

As the preeminent nuclear watchdog under the UN, the IAEA is entrusted with the task of upholding the principles of the Nuclear Non-Proliferation Treaty of 1970. It was established as an autonomous organisation on July 29, 1957, at the height of the Cold War between the U.S. and the Soviet Union. Its headquarter is in Vienna, Austria. Hence, statement 2 is correct.

Answer: B

Explanation:

After the success of Cyrus and indigenous reactor with the name Dhruva was developed so as to have an indigenous source of Pu for the weapons. The first nuclear test was in May-1974 with the name operation Smiling Buddha which was described as a peaceful nuclear explosion by PM Gandhi, their explosion was carried out all of them were fission devices and sub-kiloton devices. Hence, statement 1 is correct while statement 2 is incorrect.