Explanation:

- The Chairman of the Constituent Assembly was responsible for leading the process of framing the Constitution of India.

- Option 1: Dr. Rajendra Prasad

- Dr. Rajendra Prasad was indeed the Chairman of the Constituent Assembly.

- He later became the first President of India.

- Option 2: C. Rajagopalachari

- He was the last Governor-General of India but not associated with the Constituent Assembly as its chairman.

- Option 3: Pt. Jawaharlal Nehru

- He was a prominent leader in the Assembly and eventually the first Prime Minister of India.

- Option 4: Dr. B.R. Ambedkar

- He chaired the Drafting Committee and played a crucial role, but wasn't the Chairman of the Assembly.

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