The correct option is this: THAT HIS MOTHER'S ACTIVITIES SUGGEST AN END TO HER GRIEF.
Extremely Loud and Incredibly Close is a novel written by Jonathan Safran Foer in 2005. It is a story of a boy of nine years of age named Oskar, whose father was killed in the September 11 terrorist attacks in America. The event threw the whole family into mourning; Oskar's mother was especially consumed with grief. Oskar is the narrator in the story. In the excerpt given above, the narrator is making the assumption that his mother is already coming out of her grief.