The correct answer is Dr Rajendra Prasad.The Constitution of India was drafted by the Constituent Assembly.It was implemented under the Cabinet Mission Plan on 16 May 1946. The members of the Constituent Assembly were elected by the provincial assemblies by a single, transferable-vote system of proportional representation. Dr Rajendra Prasad was the president of the constituent assembly.Additional InformationThe members of the Constituent Assembly were elected by Provincial legislative councils.They elected people from the whole country to represent every area.It was elected in December and the first meeting in 1946.It came to force on 26th January 1950. Dr BR Ambedkar was the chairman of the Drafting Committee.