The Chairman of Atomic Energy Commission is

The Atomic Energy Commission (AEC) is India's apex policy-making and executive body for nuclear research and atomic energy, established in 1948 and functioning under the Department of Atomic Energy (DAE). By long-standing practice, whoever holds the post of Secretary, DAE, also concurrently serves as Chairman of the AEC, and this dual post has been held over time by a sequence of senior nuclear scientists and administrators.

This question is a Previous Year Question from the TPSC (Tripura Public Service Commission) Miscellaneous Posts 2015-16 preliminary examination, held on 20 December 2015. TPSC's own officially published final answer key for this paper (Test Booklet Series-B) marks the answer to this question as R. K. Sinha, who held the post of Chairman, AEC / Secretary, DAE from 30 April 2012 to 23 October 2015.

Each of the other names offered is also a genuine former holder of this same post, only in a different period:

• Srikumar Banerjee held the post from 30 November 2009 to 30 April 2012, the term immediately before R. K. Sinha.

• Sekhar Basu took charge of the post on 23 October 2015 and served until 17 September 2018, immediately after R. K. Sinha.

• Anil Kakodkar held the post from 2000 to 2009, two terms before R. K. Sinha.

One timing nuance is worth flagging for fairness: this exam was actually held on 20 December 2015, by which date Sekhar Basu had already taken charge (23 October 2015) from R. K. Sinha. TPSC's own official answer key nonetheless names R. K. Sinha as correct, most likely because the paper had been finalised before the October 2015 handover. For this specific Previous Year Question, the exam's own official answer key is treated as authoritative, so R. K. Sinha is the correct answer here.