Assertion (A): The effect of labour participation in the Indian nationalist upsurge of the early 1930s was weak. Reason (R): The labour leaders considered the ideology of Indian National Congress as bourgeois and reactionary.

The correct option is A because both statements are historically accurate and the reason directly explains the assertion.

Assertion A is true because during the Civil Disobedience Movement of the early 1930s, the participation of the working class was generally low compared to the Non Cooperation Movement. Major industrial centers like Mumbai saw some activity, but overall labor involvement remained limited.

Reason R is true and provides the explanation for this weak participation. During this period, the communist and radical left wing influence on labor unions was at its peak. These leaders viewed the Indian National Congress as a party representing the interests of the bourgeoisie or the capitalist class. They believed that the Congress leadership would compromise with British imperialism at the expense of workers rights. Consequently, the communist led unions officially distanced themselves from the Congress led nationalist struggle, leading to the weak participation mentioned in the assertion.