Explanation:

For the first time while explaining the meaning of the “Swaraj” mahatma Gandhi had indicated in 1922 that constitution of India would be drafted by the Indians.
For the first time, the constitution for India was drafted by Nehru Committee in 1928. In the Lahore session of 1929, Congress adopted the Poorna Swarajya.
In 1934, the demand for a constituent assembly was raised for the first time, which was later became an official demand in 1935. This demand was accepted in August 1940 offer by the British.
On august 8, 1940, a statement was made by the by the Viceroy, Lord Linlithgow, on the expansion of the Governor-General’s Executive Council and the establishment of a War Advisory Council. This offer also promised for giving full weight to minority opinion, recognizing the Indians to form their own constitution.
Under the cabinet mission plan of 1946, elections were held for the first time for constituent Assembly. The Constitution of India was made by the constituent assembly and it was set up under the cabinet Mission plan on 16 May 1946.