Definition: In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.
Input: Question: How old was Reynolds when the last US forces withdrew from Vietnam? Passage:Earle L. Reynolds (October 18, 1910 – January 11, 1998) was an anthropologist, educator, author, Quaker, and peace activist. He was sent to Hiroshima by the Atomic Energy Commission in 1951 to study the effects of the first atomic bomb on the growth and development of exposed children. His professional discoveries concerning the dangers of radiation later moved Reynolds into a life of anti-nuclear activism. In 1958 he sailed with his wife Barbara, two of his three children and a Japanese yachtsman in the Phoenix of Hiroshima, a ketch he had designed himself, into the American nuclear testing zone in the Pacific. In 1961 the family sailed to the USSR to protest Soviet nuclear testing. During the Vietnam War Reynolds and his second wife Akie sailed the Phoenix to Haiphong to deliver humanitarian and medical aid to victims of American bombing.
 Links: a. Haiphong b. Vietnam War c. Quakers d. Atomic bombings of Hiroshima and Nagasaki
Output:
b