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: 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
Example Output: a

Example Input: Question: On what day did the season begin that Mark Sloan first appears? Passage:Mark first appears in season two, introduced as a highly respected otolaryngologist sub-specialized in plastic surgery and the childhood best friend of neurosurgeon Derek Shepherd (Patrick Dempsey). In his first appearance, he flirts with Meredith Grey, and Derek punches him in the face. Derek explains that Mark had an affair with his wife, Addison (Kate Walsh) while they were living in New York. Mark travels to Seattle, intent on convincing Addison to return with him to New York, but his offer is rejected and Derek declines to renew their friendship. Mark returns during season three at Addison's drunken behest, but she again rejects him once sober. Undeterred, Mark sells his successful private practice (which he previously shared with Derek) and takes over the plastics program at Seattle Grace Hospital. During Meredith's morphine rampage, Mark finds out about his nickname McSteamy which was given to him by her during his first trip to Seattle back when he attempted to get Addison back and earn Derek's friendship back. It is later revealed that Mark has at some point slept with all of Derek's sisters. Mark has a brief fling with Addison's friend, orthopedic surgeon Callie Torres (Sara Ramirez), and develops a friendship with Derek's girlfriend, intern Meredith Grey (Ellen Pompeo). It is revealed that after Derek left New York, Mark and Addison continued their relationship for two months, during which she conceived and aborted his child. Just weeks after moving to Seattle he quickly observes that Derek's true love was Meredith and tries to convince Addison that her marriage with Derek was over. Mark enters into a sixty-day abstinence pact with Addison, agreeing that if they can remain celibate for that time, Addison will give their relationship another chance. Addison ultimately breaks the pact by having sex with intern Alex Karev (Justin Chambers), and soon thereafter departs from Seattle to work in Los Angeles.
Links: a. Grey's Anatomy (season 2) b. Grey's Anatomy (season 2) c. Kate Walsh (actress) d. Callie Torres
Example Output: a

Example Input: Question: How many games did Richards play for the team that own the Championship in 2006? Passage:A youth team player at Hednesford Town, he turned professional at Blackburn Rovers in 2000. He spent the 200102 season on loan at Crewe Alexandra, Oldham Athletic, and Halifax Town. He then spent much of the 200203 season on loan at Swansea City, before he was allowed to join Northampton Town in summer 2003. He scored eleven goals for the club in 200304, though was sent out on loan to Rochdale in the latter half of the 200405 campaign after he found himself struggling with injury. He joined Barnsley in August 2005, and went on to score twelve goals in 200506, helping the club win promotion to the Championship via the play-offs. Released at the end of the 200607 season, he signed with Port Vale in June 2007. After five goals in 200708, he became the club's top-scorer for four seasons running with 11 goals in 200809, 22 goals in 200910, 20 goals in 201011, and 17 goals in 201112. He signed with Chesterfield in May 2012, and played for the club in the 2014 final of the League Trophy, before helping them to win the League Two title in 201314. He returned to Northampton Town in May 2014, and finished as the club's top-scorer for two consecutive seasons, helping Northampton to win the League Two title in 201516. He signed with Swindon Town in January 2018 and after one-and-a-half seasons with Swindon moved on to Cambridge United in August 2019.
Links: a. Swindon Town F.C. b. EFL Trophy c. Barnsley F.C. d. Crewe Alexandra F.C.
Example Output:
c