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: Descriptions of T. redivivum in John Cassin's 1856 book Illustrations of the Birds of California, Texas, Oregon, British, and Russian America led later ornithologists to conclude that at least three of the birds described were actually the crissal thrasher. When an army surgeon working in New Mexico sent Cassin specimens of a bird that _he_believed to be the California thrasher, Cassin sent the specimens to Spencer Baird at the Smithsonian Institution. <sep>, Pronoun: he <sep>, A: Cassin <sep>, B: Spencer Baird

Neither