Instructions: 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: He has received numerous awards and grants besides those listed here. He and co-author Kai Bird shared the Pulitzer Prize for Biography or Autobiography in 2006, for their book on Robert Oppenheimer 's life, titled . Sherwin worked on the book for two decades before Bird, a writer (and not a historian), came on to collaborate in piecing all _his_ research together. <sep>, Pronoun: his <sep>, A: Sherwin <sep>, B: Bird
Output:
A