B. Bilbo. Because, after Bilbo took the ring, his first thought was to kill Gollum but after he heard him crying thief and crying for his "precious" [which was actually a "birthday present" from his close relative(He strangled him for it)], he was sorry for him and decided not to.
Fun Fact!: Smeagol (Gollum) was actually a hobbit at first, and lived a lot longer than any hobbit could!