Explanation:

- Option 1: Bhagat Singh

- Bhagat Singh was indeed accused in the murder of British police officer John Saunders in 1928, along with Rajguru and others.

- This was part of a larger revolutionary movement against British rule in India.

- Bhagat Singh aimed to avenge the death of Lala Lajpat Rai.

- Option 2: Aurobindo Ghosh

- Aurobindo Ghosh was an Indian nationalist and philosopher, but he was not connected to Saunders' murder.

- His revolutionary activities were decades earlier.

- Option 3: Madan Lal Dhingra

- Dhingra was involved in a different incident, the assassination of British official William Hutt Curzon Wyllie in London in 1909.

- Option 4: Basant Kumar

- This name is not associated with the Saunders murder case.