Statements made by persons to the Commission.

No statement made by a person in the course of giving evidence before the Commission or an officer or agency, referred to in clause (a), or the person referred to in clause (b) of sub-section (1) of section 12, shall subject him to, or be used against him in, any civil or criminal proceedings except a prosecution for giving false evidence by such statement: Provided that the statement, - (a) is made in reply to a question, which is required by the Commission or such officer or agency or such person to answer; or (b) is relevant to the subject matter under investigation.