The correct answer is (c) Udham Singh.
Udham Singh was an Indian nationalist who assassinated Michael O’Dwyer, the former Lieutenant Governor of Punjab, on 13 March 1940, in London, to avenge the Jallianwala Bagh massacre.
Prithvi Singh Azad was an Indian revolutionary who was involved in the Ghadar Party. He was executed by the British in 1915.
Sardar Kishan Singh was an Indian freedom fighter who was involved in the Non-Cooperation Movement. He was imprisoned by the British for his activities.
Sohan Singh Josh was an Indian poet and freedom fighter who was involved in the Ghadar Party. He was imprisoned by the British for his activities.
The Jallianwala Bagh massacre was a massacre of unarmed Indian civilians by British Indian Army soldiers on 13 April 1919 in the Jallianwala Bagh garden in Amritsar, Punjab, India. The British Indian Army under the command of Brigadier-General Reginald Dyer fired on a crowd of Indian civilians without warning, killing at least 379 people and injuring over 1,200 others. The massacre was one of the most infamous incidents of British colonial rule in India.