(a). C. Rajagopalachari
(b). Dr. B.R. Ambedkar
(c). T.T. Krishnamachari
(d). Dr. Sachchidananda Sinha
Explanation:
Dr. Sachchidananda Sinha served as the provisional or temporary President of the Constituent Assembly before Dr. Rajendra Prasad was elected as the permanent president.
His position and the context:
- Provisional President: He was chosen as the temporary President of the Constituent Assembly on December 9, 1946, during its first meeting.
- Reason for Temporary Role: Since the Assembly was new, a formal election for a permanent president hadn't been conducted yet. Dr. Sinha, being the eldest member of the Assembly, was chosen to preside over the initial proceedings following a common practice in parliamentary systems.
- Short Tenure: His role as the Provisional President lasted only two days. On December 11, 1946, Dr. Rajendra Prasad was formally elected as the permanent President.
Why other options are incorrect:
- C. Rajagopalachari: While a prominent figure in Indian independence, he wasn't associated with the Constituent Assembly's presidency. He served as the last Governor-General of India.
- Dr. B.R. Ambedkar: Though crucial to the Constitution's creation, Dr. Ambedkar chaired the Drafting Committee, responsible for drafting the final document.
- T.T. Krishnamachari: An important member of the Assembly, he didn't hold the presidency. He later became India's Finance Minister.
So, the correct answer is Option (d).