Correct Option: B

In 1929, Ambedkar made the controversial decision to co-operate with the all-British Simon Commission which was to look into setting up a responsible Indian Government in India. The Congress decided to boycott the Commission and drafted its own version of a constitution for free India. The Congress version had no provisions for the depressed classes. Ambedkar became more skeptical of the Congress's commitment to safeguard the rights of the depressed classes. He attended all the three Round Table Conferences in London and forcefully argued for the welfare of the "untouchables".