19.
The answer is: B
Explanation
The correct option is B: Lahore Conspiracy case.
Bhagat Singh, Rajguru and Sukhdev were hanged for their role in the assassination of British police officer John Saunders in Lahore on December 17, 1928.
They mistook Saunders for James Scott, the superintendent of police who had ordered the lathi charge that led to the death of Lala Lajpat Rai.
The trio was also involved in other revolutionary activities, such as throwing bombs in the Central Legislative Assembly and founding the Hindustan Socialist Republican Association.
They were sentenced to death by a special tribunal and executed on March 23, 1931, despite massive public protests. Their martyrdom inspired many Indians to join the freedom struggle and is commemorated as Shaheed Diwas every year.