Step 1: Understanding the question.
The question asks about the current Chairperson of the Securities and Exchange Board of India (SEBI).
Step 2: Analyzing the options.
(A) Raghuram Rajan: He is a former RBI Governor, not SEBI Chairperson.
(B) Urjit Patel: He is also a former RBI Governor.
(C) Madhabi Puri Buch: Correct — She is the current Chairperson of SEBI and the first woman to hold this position.
(D) Nirmala Sitharaman: She is the Finance Minister of India.
Step 3: Conclusion.
The current Chairperson of SEBI is Madhabi Puri Buch.