The idea of a constituent assembly to frame a constitution for India was first proposed by the Swaraj Party in 1934.

Option 1 is, therefore, the correct answer.

The Swaraj Party was a group of activists, part of the Indian independence movement, who proposed this concept as a way of granting India complete self-rule.

Option 2 suggests that it was the Congress Party in 1936, however, that`s not correct as the Congress Party actually endorsed the idea proposed by the Swaraj Party in their 1935 session.

Option 3 suggests that it was the Muslim League in 1942, but this isn`t accurate either. At this time, the Muslim League was focused on the concept of having separate nations for Hindus and Muslims, not on the formation of a constituent assembly.

Option 4 is the All Parties Conference in 1946, which again is incorrect because it was only after two years of discussion around the idea of a constituent assembly that the All Parties Conference eventually supported it in 1946.

So, to summarize, it was the Swaraj Party in 1934 that initially proposed the idea of a constituent assembly for framing India`s constitution.