Correct Option (A):
Assertion (A) states that the Congress Ministries in all the provinces resigned in 1939. This is correct. Following the provincial elections of 1937 under the Government of India Act, 1935, the Indian National Congress formed ministries in seven out of eleven provinces. With the outbreak of the Second World War in September 1939, Viceroy Lord Linlithgow declared India a belligerent nation without consulting Indian political leaders or the elected provincial governments. As a protest against this unilateral action and the denial of India's right to self-determination, the Congress ministries resigned from office between October and November 1939.
Reason (R) states that the Congress did not accept the Viceroy's decision to declare war against Germany in the context of the Second World War. This is also correct. The Congress viewed the Viceroy's declaration of war without Indian consent as an affront to democratic principles and India's aspirations for self-rule. They demanded a clear declaration from the British government regarding India's independence after the war as a condition for their support. As no satisfactory assurance was provided, the Congress decided to withdraw its ministries.
Reason (R) is the correct explanation of Assertion (A). The non-acceptance of the Viceroy's unilateral decision to involve India in the war, coupled with the British government's refusal to offer concrete assurances of post-war independence, directly led to the resignation of the Congress ministries.
Incorrect Options:
Options (2), (3), and (4) are incorrect because both Assertion (A) and Reason (R) are factually true, and Reason (R) accurately explains the cause for Assertion (A). Therefore, statements suggesting that R is not the correct explanation, or that either A or R is false, are incorrect.