The correct answer is option 2, A.O. Hume. A.O. Hume, a retired British civil servant, initiated the movement to form the Indian National Congress. Hume believed that there was a need for an organized political platform to voice the concerns and grievances of the Indian people under British rule. Consequently, he held a meeting on December 28, 1885, which marked the formation of the Indian National Congress. The first session of the Congress was held in Bombay (now Mumbai) in December 1885, with W.C. Banerjee as its president. Although Annie Besant and Mahatma Gandhi played significant roles in the Indian independence movement later on, they were not the initiators of the Congress.