The Constituent Assembly was responsible for drafting the Constitution of India after independence. The Drafting Committee, which played a crucial role in framing the Constitution, was headed by Dr. Bhimrao Ambedkar. He is often referred to as the "Father of the Indian Constitution" due to his significant contributions to its drafting and structure. The other options are notable figures in Indian history but did not serve as the chairman of the Drafting Committee: - Jawaharlal Nehru was the first Prime Minister of India. - Dr. Rajendra Prasad was the first President of India. - Sardar Vallabhbhai Patel was the Deputy Chairman of the Constituent Assembly and played a key role in integrating princely states into the Indian Union. Answer: $\boxed{\text{Dr. Bhimrao Ambedkar}}$