(a) Some use uranium and others use thorium

(b) Some use imported uranium and others use domestic supplies.

(c) Some are operated by foreign enterprises and others are operated by domestic enterprises

(d) Some are State-owned and others are privately-owned

Ans: b

Explanation: 

Safeguards are a main plank in the global nuclear security regime because they allow the IAEA to make sure that nuclear materials like uranium and plutonium in the civil power sector are never used in military programs.

An Agreement between the Government of India and the IAEA for the Application of Safeguards to Civilian Nuclear Facilities (nuclear safeguards agreement ) was signed in 2009.

Under this agreement India will decide on the reactors to be placed under IAEA safeguards only after assessing if these will be fuelled by uranium procured from abroad. 

By placing the reactors under the IAEA safeguards, India gives the international nuclear energy watchdog access to them. This step was taken by the country in 2014 to demonstrate that its nuclear energy programme was for peaceful purposes. 

This is a necessary step under the Indo-US nuclear deal.

There are at present 22 operational reactors in India, of which 14 are under the International Atomic Energy Agency (IAEA) safeguards.

Hence, option b is correct.

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