Correct Option: D

Ganesh Vasudev Mavalankar popularly known as Dadasaheb was an independence activist, the President of the Central Legislative Assembly, then Speaker of the Constituent Assembly of India, and later the first Speaker of the Lok Sabha, the lower house of the Parliament of India. Mavalankar remained the President of the Central Legislative Assembly till the midnight of August 14–15, 1947 when, under the Indian Independence Act 1947, the Central Legislative Assembly and the Council of States ceased to exist and the Constituent Assembly of India assumed full powers for the governance of India. Just after independence, Mavalankar headed a committee constituted on August 20, 1947 to study and report on the need to separate the Constitutionmaking role of the Constituent Assembly from its legislative role.