The well-known film "Chittagong" directed by Bedabrata Pain is primarily based on the life of Subodh Roy. Subodh Roy was a revolutionary freedom fighter and one of the key leaders of the Chittagong uprising in 1930 against British colonial rule in India.

Option - 1: Subodh Roy

This is the correct answer. Subodh Roy`s life and role in the Chittagong uprising are the main focus of the film.

Option - 2: Binod Bihari Chowdhury

This option is incorrect. Binod Bihari Chowdhury was also a prominent freedom fighter involved in the Chittagong uprising, but the film does not primarily focus on his life.

Option - 3: Preetilata Wadedar

This option is incorrect. Preetilata Wadedar was a brave female revolutionary who participated in the Chittagong uprising, but the film does not primarily revolve around her life.

Option - 4: Ganesh Ghosh

This option is incorrect. Ganesh Ghosh was another key leader of the Chittagong uprising, but the film does not primarily center around his life.

Therefore, the correct answer is option