Explanation:

Option B is correct: During the British colonial era, Dr. B.R. Ambedkar held a stance opposing the Congress. However, upon Mahatma Gandhi's counsel, he was invited to become a part of the Union Cabinet as the Law Minister after India's independence. In this role, he assumed the chairmanship of the Drafting Committee for the Constitution. Collaborating alongside him were two additional legal experts, K.M. Munshi representing Gujarat and Alladi Krishnaswamy Aiyar representing Madras, both of whom made pivotal contributions to the Constitution-drafting process. Ambedkar himself had the responsibility of guiding the Draft Constitution through the Assembly. This took three years in all, with the printed record of the discussions taking up eleven bulky volumes.