The correct answer is: B. 2 Only
The Speaker of Lok Sabha is the ex-officio Chairperson of the Business Advisory Committee. The Business Advisory Committee is a committee of members of the Lok Sabha that advises the Speaker on the time to be allotted for the discussion of different items on the agenda of the House.
The Speaker of Lok Sabha is not the ex-officio Chairperson of the Railway Convention Committee or the Public Accounts Committee. The Railway Convention Committee is a committee of members of the Lok Sabha and the Rajya Sabha that advises the government on matters relating to railways. The Public Accounts Committee is a committee of members of the Lok Sabha that examines the accounts of the government.