Dr Devender Singh, Nagender Ram Nath and Aatma Ram were the founder of

Suket Movement
Sirmaur Riyasati Praja Mandal
Indian National Congress
None of the above

The correct answer is: B. Sirmaur Riyasati Praja Mandal

Dr Devender Singh, Nagender Ram Nath and Aatma Ram were the founders of the Sirmaur Riyasati Praja Mandal, a political party that was formed in 1938 to fight for the rights of the people of Sirmaur State. The party was successful in achieving its goal of independence for Sirmaur State, which was merged with the Indian Union in 1948.

The other options are incorrect. The Suket Movement was a movement that was started in 1920 by the people of Suket State to fight for their rights. The Indian National Congress is a political party that was founded in 1885 by Allan Octavian Hume.