Definition: In this task, you will be presented with a text, a pronoun from the text, and two candidate names. You should determine what the pronoun refers to and classify the answers into A, B, or Neither. A and B here are referring to option A and option B. Position of the pronoun in the text is showed within two "_"s.
Input: Males from the northern group, led by the alpha male Darius, start patrolling into the southerners' territory and then start to kill, with extreme cruelty, the rival males - one an old chimpanzee called Mr Jeb, and the other Muffin, an adolescent. What she sees brings Hope herself into conflict with Mallabar, and threatens the very existence of Grosso Arvore research project and _his_ lifelong study of primates. <sep>, Pronoun: his <sep>, A: Darius <sep>, B: Jeb

Neither