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.

Example Input: Question: Who is the current president of the instute where Fisher first had a  had a psychotic episode including hallucinations and delusions while working as a psychiatrist? Passage:The co-founder and executive director is Daniel B. Fisher, now a board-certified psychiatrist. A graduate of Princeton University, he completed a PhD in biochemistry at the University of Wisconsin, medical training at George Washington University, and a psychiatric residency at Harvard Medical School. While working as a biomedical researcher at the National Institute of Mental Health before he was a psychiatrist, Fisher had a psychotic episode including hallucinations and delusions. After three months at Bethesda Naval Hospital at age 25, which included forced seclusion and antipsychotic haloperidol, he was discharged with a diagnosis of schizophrenia. He was involuntarily hospitalized three times. He reports being influenced by those who were able to show they cared about the person inside and gave him hope that he might some day recover. He went on to become a psychiatrist. He was told during psychiatric training that "You can’t talk to an illness" but believed that talking to the person inside is a key method for building trust and recovery. He has since worked as a psychiatrist in hospitals and clinics, while also being a part of the consumer movement. He said that a very significant part of the reason for becoming a psychiatrist was wanting to bring to the field what he wished had been there when he was going through psychosis He was a member of the White House Commission on Mental Health, 2002-03.
 Links: a. National Institute of Mental Health b. Walter Reed National Military Medical Center c. Schizophrenia d. Walter Reed National Military Medical Center
Example Output: a

Example Input: Question: How many casualties had the Japanese Army suffered by the time Vincent was sent to Tokyo? Passage:Born the son of Colonel Arthur Hare Vincent and Elizabeth Rose Manson and educated at Wellington College and the Royal Military Academy, Woolwich, Vincent was commissioned into the Royal Artillery as a second lieutenant on 24 July 1891. He was promoted to lieutenant on 24 July 1894 and to captain on 13 February 1900. He served with the China Expeditionary Force in late 1900 and then in the Second Boer War in South Africa. Following the end of the war, Vincent left Point Natal for India on the SS Ionian in October 1902 with other officers and men of the J Battery Royal Horse Artillery, and after arrival in Bombay, was stationed in Meerut, Bengal Presidency. In 1903, Vincent was sent to Tokyo to learn Japanese: he served as British military attaché with the Japanese Army during the Russo-Japanese War and, from 1 March 1904, was attached to the 2nd Division of the First Japanese Army in Manchuria.
 Links: a. Imperial Japanese Army b. Second lieutenant c. Second Boer War d. Royal Military Academy, Woolwich
Example Output: a

Example Input: Question: Which of the cities that Charles K. Erwin lived in is the oldest? Passage:Born in Washington, Lycoming County, Pennsylvania, Erwin settled in Portage, Wisconsin in 1853. From 1855 to 1868, Erwin lived in Jo Daviess County, Illinois and then in Stephenson County, Illinois. During the American Civil War, Erwin served in the 45th Illinois Volunteer Infantry Regiment. In 1868, Erwin moved to Tomah, Wisconsin and was in the mercantile business. From 1879 to 1882 and 1886, Erwin served on the Tomah Board of Education and was president of the school board. From 1882 to 1889, Erwin served in the Wisconsin State Senate and was a Republican. In 1889, Erwin served as postmaster for Tomah, Wisconsin. In 1902, Erwin moved with his family to Milwaukee, Wisconsin. Erwin died suddenly in Savanna, Illinois just as he was about get on a train for a trip to Omaha, Nebraska.
 Links: a. Portage, Wisconsin b. Stephenson County, Illinois c. Lycoming County, Pennsylvania d. Milwaukee
Example Output:
a