Answer :
B. He provides a twist to the tragic tale his niece tells their guest.
Vera, Mrs Sappleton's niece, fabricates an untrue tale on learning that Mr Framton does not know any member of the Sappleton family personally and is only carrying a letter of introduction to her aunt. In her tale, the present day falls on the tragic third anniversary of the day when the Sappleton men ventured out into the jungle for a hunt never to return back. She further tells Mr Framton that her aunt believes that all three of them will return through the open window one day.
Vera describes that Mr Sappleton also carried his white waterproof coat over his arm. As dusk approaches, and Mr Framton sees three figures approaching the open window, one of them carrying a white coat over his arm. He grows quite certain that he has seen the ghost of Mr Sappleton.
Mr Sappleton's role in the story is to add the touch of truthfulness to Vera's story. He adds a twist to Vera's tragic tale by being one of the members of the ghostly hunting party.
