Which one of the following is not correctly matched ?

The odd one out is A. The Indian Sociologist was a monthly journal started by Shyamji Krishna Varma in London around 1905, not a work by Bhagat Singh. Bhagat Singh's known writings are essays like Why I Am an Atheist and Ideal of Socialism, so the pairing is wrong.

The other three pairings are correct:

• B: Sachindranath Sanyal, a founder of the Hindustan Republican Association, wrote Bandi Jivan (1922), a classic account of prison life and revolutionary commitment.
• C: Lala Ramsaran Das is associated with Dreamland, which is the correct match here.
• D: Bhagwati Charan Vohra wrote The Philosophy of the Bomb (1930), a key text of revolutionary thought in the Hindustan Socialist Republican Association.

The core concept is the nationalist and revolutionary press and literature of early twentieth-century India. For Mains, it is useful for questions on how ideas of armed struggle, socialism and anti-colonial nationalism were spread through writing, and on the role of diaspora publications like those from London.

Trap: aspirants see a famous revolutionary's name and assume he authored every related title. Check whether the item is a person's work or a periodical.