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: What is the current age of the U.S. Army soldier who were held captive by the Taliban for five years? Passage:Serial is an investigative journalism podcast hosted by Sarah Koenig, narrating a nonfiction story over multiple episodes. The series was co-created and is co-produced by Koenig and Julie Snyder and developed by This American Life. Season one investigated the 1999 murder of Hae Min Lee (Hangul: 이해민), an 18-year-old student at Woodlawn High School in Baltimore. Season two focused on Sergeant Bowe Bergdahl, an American Army soldier who was held for five years by the Taliban, and then charged with desertion. Season three, which debuted in September 2018, explores cases within the Justice Center Complex in the Cleveland area. Serial ranked number one on iTunes even before its debut and remained there for several weeks. Serial won a Peabody Award in April 2015 for its innovative telling of a long-form nonfiction story. As of September 2018, episodes of seasons one and two have been downloaded over 340 million times, establishing an ongoing podcast world record.
 Links: a. Cleveland b. Bowe Bergdahl c. Bowe Bergdahl d. Desertion
Example Output: b

Example Input: Question: Who won the World Cup where the Costa Rican team had a prominent performance? Passage:Since the late 1980s, the team has continuously been visible as a solidly competitive side, with a prominent performance in the 1990 FIFA World Cup in Italy, making it to the knockout stage in their debut after finishing second in their group during the first phase, below Brazil. They also managed to qualify for the 2002 and 2006 FIFA World Cups. In 2014, Costa Rica made their best performance in history by finishing first in their group that consisted of three former World Cup champions: Uruguay, Italy, and England. During the Round of 16 they defeated Greece 5–3 via a penalty shootout after a 1–1 draw. Moreover, during the match against a much better team, Navas saved more than 15 shots due to the Costa Rican very weak defense. The match was characterized as "Navas vs Greece". They reached the quarterfinals for the very first time as the Ticos were defeated by the Netherlands also in a penalty shootout (3–4) after a scoreless draw on 5 July. Their 2018 World Cup campaign ended in a 4th place group stage exit with their only point coming from a 2-2 draw vs Switzerland.
 Links: a. 2006 FIFA World Cup b. 1990 FIFA World Cup c. 2006 FIFA World Cup d. Keylor Navas
Example Output: b

Example Input: Question: What is the home stadium of the team that Faraki was manager of that he led to promotion? Passage:During Branko Ivankovic's time as Team Melli manager, Faraki was the assistant manager. He was also the head coach of the Iran national under-23 football team from 2003 till 2006. He was manager of Kaveh Tehran which led the club to promotion to the Azadegan League. He was appointed as head coach of Naft Tehran on 1 July 2010 and secured the team from relegation in his first season at the club. At the second season, he led the club to the 5th place, which was their best league end until 2014. He not renewed his contract with the team and signed a two years contract with Foolad on 5 June 2012. He led Foolad to the AFC Champions League for the second time since 2006 after they finished 4th in 2012–13. In 2013–14 season, Faraki's side won the league, finishing the season with 57 points, two more from runners-up Persepolis. He resigned as Foolad's manager at the end of the season because he needs an imminent knee operation.
 Links: a. 2012–13 Persian Gulf Cup b. Branko Ivanković c. Sanati Kaveh Tehran F.C. d. Persepolis F.C.
Example Output:
c