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.

Ex Input:
Question: How many years did the owner of the private observatory live? Passage:It would seem that Gill's interests lay elsewhere since after a few years he sold the business, and then spent time equipping Lord Lindsay's private observatory at Dun Echt, Aberdeenshire. In 1874, Gill joined the expedition to Mauritius to observe the transit of Venus. Three years later he went to Ascension Island to observe a near approach of Mars and to calculate its distance. While carrying out these laborious calculations, he was notified of his appointment to the Cape Observatory, which, over the following 27 years he was to refurbish completely, turning it into a first-rate institution. Gill was a meticulous observer and had a flair for getting the best out of his instruments. His solar parallax observations with a heliometer and his calculations of distances to the nearer stars, are testimony to his outstanding work. He recruited Robert Innes to the Cape Observatory.
Links: a. South African Astronomical Observatory b. Aberdeenshire (historic) c. James Lindsay, 26th Earl of Crawford d. South African Astronomical Observatory

Ex Output:
c

Ex Input:
Question: Once a member of the Birmingham Repertory Theatre, what was Derek Jacobi's first action role? Passage:While in the sixth form, he starred in a production of Hamlet, which was taken to the Edinburgh Festival Fringe and very well regarded. At 18 he won a scholarship to the University of Cambridge, where he read history at St John's College and earned his degree. Younger members of the university at the time included Ian McKellen (who had a crush on him"a passion that was undeclared and unrequited", as McKellen relates it) and Trevor Nunn. During his studies at Cambridge, Jacobi played many parts including Hamlet, which was taken on a tour to Switzerland, where he met Richard Burton. As a result of his performance of Edward II at Cambridge, Jacobi was invited to become a member of the Birmingham Repertory Theatre immediately upon his graduation in 1960.
Links: a. Trevor Nunn b. Birmingham Repertory Theatre c. Trevor Nunn d. Richard Burton

Ex Output:
b

Ex Input:
Question: How many years passed between Jackson's first single and her last? Passage:The singles discography of Wanda Jackson, an American recording artist, consists of seventy-eight singles, nine international singles, one charting b-side, and three music videos. In 1954 at age sixteen, she signed as a country artist with Decca Records. Her debut single was a duet recording with Billy Gray which reached the eighth spot on the Billboard Hot Country Singles chart, also in 1954. Refusing to tour until completing high school, Jackson's further singles for Decca failed gaining success. She signed with Capitol Records in 1956 and began incorporating rock and roll into her musical style. Jackson's first Capitol single exemplified this format ("I Gotta Know") and became a national top-twenty country hit. Follow-up rock singles between 1957 and 1959 failed gaining enough attention to become hits including, "Hot Dog! That Made Him Mad", "Fujiyama Mama", and "Honey Bop". In 1960 however, the rock and roll-themed, "Let's Have a Party", became Jackson's first Billboard top-forty pop hit after it was picked up by an Iowa disc jockey.
Links: a. You Can't Have My Love b. Single (music) c. Discography d. Billboard (magazine)

Ex Output:
b