The correct option is C Indira Gandhi
During the Khalistan Movement, Indira Gandhi was the Prime Minister of India. She was the one who commissioned Operation Blue Star on 01 June 1984, to supress the Khalistan Uprising.
Jawaharlal Nehru was the first Prime Minister of India and lived before his daughter, Indira Gandhi, took this position. Rajiv Gandhi was his son, and he replaced her.
Sonia Gandhi is a current leader of the Indian National Congress party.