The pamphlet entitled ‘Why I am an atheist?’ was written by

The correct answer is (a) B.K. Dutt.

Bhagat Singh, Rajguru, and Yashpal were all members of the Hindustan Socialist Republican Association (HSRA), a revolutionary organization that fought for Indian independence from British rule. They were all executed in 1931 for their role in the assassination of a British police officer.

B.K. Dutt was

also a member of the HSRA, and he was imprisoned with Bhagat Singh, Rajguru, and Yashpal. While in prison, he wrote the pamphlet entitled ‘Why I am an atheist?’ in which he argued that religion is a tool of oppression and that atheism is the only way to achieve true freedom.

The other options are incorrect because they are not the authors of the pamphlet entitled ‘Why I am an atheist?’.