Detailed explanation and options for the selected question.
Dr. B.R. Ambedkar is considered the "father of the Indian Constitution" due to his significant role as the principal architect of the Constitution. Option "Jawaharlal Nehru" is incorrect as Nehru was the first Prime Minister of India but not involved directly in the drafting. Option "Mahatma Gandhi" was the leader of the independence movement but did not contribute to drafting the Constitution. Option "Subhas Chandra Bose" was a prominent freedom fighter but not involved in the Constitution-making process.