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: Which of the regiments that Ellwood served in was the largest? Passage:Ellwood graduated from Duntroon in 1990 and was commissioned into the Royal Australian Infantry Corps. His early career included postings as a platoon commander in the 2nd/4th Battalion, Royal Australian Regiment and as an instructor in field training and tactics at Duntroon, before he was seconded to the British Army from 1998 for a two-year exchange with the Irish Guards, then stationed in Germany. During the secondment he deployed as part of the NATO intervention in the Kosovo War in 1999, serving as second-in-command of an armoured infantry company in the King's Royal Hussars Battle Group. For his service in Kosovo, Ellwood was awarded a Commander British Forces Commendation. He returned to Australia as a company commander and operations officer in the 5th/7th Battalion, Royal Australian Regiment (5/7RAR). Ellwood commanded B Company on operations in East Timor from October 1999 to April 2000, when 5/7RAR deployed with the International Force East Timor.
Links: a. 2nd/4th Battalion, Royal Australian Regiment b. Kosovo War c. 2nd/4th Battalion, Royal Australian Regiment d. King's Royal Hussars

Ex Output:
a

Ex Input:
Question: How many people did Arnstadt command as a company commander of the 6th border company in Dermbach? Passage:In June 1949, Arnstadt registered for service with the Volkspolizei, the police force of the Soviet Occupation Zone, becoming an Anwarter der VP (police cadet) with the Kasernierte Volkspolizei in Gotha. In March 1950, Arnstadt was appointed to the German Border Police (Deutsche Grenzpolizei) in Dermbach, patrolling the Inner German border with West Germany. In 1952, Arnstadt failed his first attempt to become an officer at the police school in Sondershausen. In 1953, his marriage ended in divorce, with his two children Veronika and Uwe staying with the mother, and remarried shortly after. In 1954, Arnstadt passed his officer training at Sondershausen and was appointed the rank of Unterleutnant, and the following year was promoted to lieutenant. Arnstadt functioned as a recruiter for the German Border Police until 1957 when he was appointed as a company commander of the 6th border company in Dermbach. Arnstadt was responsible for a section of the border at Wiesenfeld, a region of Bezirk Suhl in the Rhon Mountains at the westernmost point of the Warsaw Pact. Arnstadt's section contained the highly-strategic Fulda Gap, which aroused the special interest of NATO, and a short distance from the US Army's Observation Post Alpha. Arnstadt moved with his wife to Wiesenfeld and in April 1957 became an unofficial collaborator (Geheimer Informator) of the Ministry for State Security (Stasi) until this relationship was ended fourteen months later.
Links: a. Company commander b. Inner German border c. Dermbach d. Kasernierte Volkspolizei

Ex Output:
a

Ex Input:
Question: Did the album Spirit of Eden have any hit singles? Passage:In 1986, Talk Talk, then a three-piece band consisting of leader and singer Mark Hollis alongside drummer Lee Harris and bassist Paul Webb, released their third album The Colour of Spring, which saw the band shift from their earlier, synthpop-oriented sound and featured a more organic art rock sound, where musicians improvised with their instruments for many hours, then Hollis and producer Tim Friese-Greene edited and arranged the performances to get the sound they wanted. A total of sixteen musicians appeared on the album. It became their most successful album, selling over two million copies and prompting a major world tour. Nonetheless, for their next album Spirit of Eden (1988), the band chose to work towards an even more unconventional and uncommercial direction. The album was compiled from a lengthy recording process at London's Wessex Studios between 1987 and 1988 where the band worked again with Friese-Greene and engineer Phill Brown. Often working in darkness, the band recorded many hours of improvised performances which were heavily edited and re-arranged into the final album.
Links: a. Spirit of Eden b. Art rock c. The Colour of Spring d. Musical improvisation

Ex Output:
a