Answer : 2. "गणेश वासुदेव मावलंकर"
Explanation :

Ganesh Vasudev Mavalankar (27 November 1888 – 27 February 1956) popularly known as Dadasaheb was an independence activist, the President (from 1946 to 1947) of the Central Legislative Assembly, then Speaker of the Constituent Assembly of India, and later the first Speaker of the Lok Sabha,