The correct option is D 23 March 1931
Bhagat Singh was trialed and sentenced to death in the Lahore Conspiracy Case in which he killed the DSP Saunders to avenge the death of Lala Lajpat Rai. Singh along with Rajguru and Sukhdev was hanged on 23 March 1931 at 7:30 pm in the Lahore jail.