(a) Two reasons for the launching of the Quit India Movement : 

(i) The Cripps Mission had failed. It seemed that the British Government was unwilling to grant self-government to the Indians. The Congress had to do something about this. 

(ii) In 1940, at Lahore, the Muslim League had officially declared their demand of a separate Pakistan. The leaders declared that the Muslims in India would not get justice from the Congress. This intensified Hindu-Muslim relations. 

(b) Three effects of the Quit India Movement launched by Gandhi in 1942 : 

(i) The Quit India Movement demonstrated the depth of nationalistic feelings: The movement exhibited the depth of nationalistic feelings and made the British realize that the days of their domination in India were numbered. People from all parts of India fought together against the British.

(ii) Setback to the British : The British officials had now realized that the British would not be able to retain their hold on India. 

(iii) Parallel Government : A significant feature of the Quit India Movement was the emergence of parallel governments in Balia in Uttar Pradesh, Midnapur in Bengal and Satara in Maharashtra. 

(c) Four clauses of the Mountbatten Plan of 1947 : 

(i) Partition of Sindh, Bengal and Punjab to be based on the decision of their Legislative Assemblies. 

(ii) There would be a referendum in NWFP and in part of Sylhet, where there was Muslim majority. 

(iii) The princely states were given freedom to join either India or Pakistan or remain independent. 

(iv) A Boundary Commission would be set up to mark out boundaries when and where required.