Solution:

An idea for a Constituent Assembly of India was proposed in 1934 by M. N. Roy, a pioneer of the Communist movement in India and an advocate of radical democracy. It became an official demand of the Indian National Congress in 1935, C. Rajagopalachari voiced the demand for a Constituent Assembly on 15th November 1939 based on adult franchise and was accepted by the British in August 1940.

On 8 August 1940, a statement was made by Viceroy Lord Linlithgow about the expansion of the Governor-General’s Executive Council and the establishment of a War Advisory Council. This offer, known as the August Offer, included giving full weight to minority opinions and allowing Indians to draft their own constitution. Under the Cabinet Mission Plan of 1946, elections were held for the first time for the Constituent Assembly.
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. The total membership of the Constituent Assembly was 389: 292 were representatives of the states, 93 represented the princely states and four were from the chief commissioner provinces of Delhi, Ajmer-Merwara, Coorg (Near Madikeri) and British Baluchistan.

9 December 1946: The first meeting of the Constituent Assembly was held in the constitution hall (now the Central Hall of Parliament House). Demanding a separate state, the Muslim League boycotted the meeting. Sachchidananda Sinha was elected temporary president of the assembly, in accordance with French practice.

11 December 1946: Rajendra Prasad was elected as president and H. C. Mukherjee was elected as vice-president of the constituent assembly. B. N. Rau was appointed as its constitutional adviser.

13 December 1946: An ‘Objective Resolution’ was moved by Jawaharlal Nehru in the assembly, laying down the underlying principles of the constitution. It finally became the Preamble of the constitution.

22 January 1947: Objective resolution unanimously adopted.

22 July 1947: National flag adopted.
15 August 1947: Indian independence achieved as the Dominion of India.
29 August 1947: Drafting Committee appointed with Dr. B. R. Ambedkar as the Chairman.
16 July 1948: Along with Harendra Coomar Mookerjee V. T. Krishnamachari was also elected as second vice-president of Constituent Assembly.
26 November 1949: Constitution passed and accepted by the assembly.
24 January 1950: “Jana Gana Mana” adopted as the national anthem, with the first two verses of “Vande Mataram” the national song. Rajendra Prasad elected the first president of India.

The assembly was chaired by Dr. Rajendra Prasad when it met as a constituent body, and by G. V. Mavlankar when it met as a legislative body. It completed the task of drafting a constitution in two years, eleven months and eighteen days, at a total expenditure of ?6.4 million.