The congress ministries resigned in seven provinces in 1939 because

The correct answer is D. The resignations were a political protest against the way India was taken into the Second World War, not a result of any of the three reasons given.

On 3 September 1939 Viceroy Linlithgow declared India at war with Germany without consulting Indian leaders. The Congress Working Committee objected, demanded a clear statement of war aims and an assurance of independence, and when this was refused, asked its provincial ministries to resign in late October and November 1939. Seven ministries, in Madras, Bombay, the United Provinces, Bihar, the Central Provinces, Orissa and the NWFP, complied.

• A is wrong. The resignations were a deliberate party decision, not a failure to form ministries elsewhere.
• B is wrong. Subhas Bose's Forward Bloc (1939) reflected left-wing pressure, but the left did not make the ministries unworkable. The decision came from the top leadership.
• C is wrong. Communal tension existed, but the resignations were not caused by riots. The Muslim League marked 'Deliverance Day' on 22 December 1939 after the resignations.

Core concept: the 1937 provincial autonomy experiment and the Congress response to the war. Mains angle: the episode deepened the Congress-League rift and is a useful thread for questions on Partition politics.

Trap: aspirants pick B because of the Forward Bloc or C because of communalism, forgetting that the trigger was the declaration of war.