Solution:

• In 1934, M N Roy first proposed the idea of a constituent assembly. The Constituent Assembly was constituted in November 1946 under the scheme formulated by the Cabinet Mission Plan.
• The Constitution of India was drafted by the Constituent Assembly, and 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.
• On 9 December 1946, in the Constitution Hall, which is now known as the Central Hall of Parliament House, the Constituent Assembly convened for the first time in New Delhi.