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 team won the title in Wotherspoon's debut season? Passage:A native of Surrey, British Columbia, Wotherspoon was selected by the Portland Winter Hawks in the second round of the 2008 Western Hockey League (WHL) Bantam Draft. He made his WHL debut as a 15-year-old in 2008–09, appearing in four games for Portland, then played four full seasons between 2009 and 2013. In his WHL career, he has appeared in 239 games in his WHL career and scored 17 goals along with 65 assists. With the Winterhawks, he appeared in the WHL championship series in three consecutive years as Portland lost the final in 2011 and 2012 to the Kootenay Ice and Edmonton Oil Kings, respectively, before finally winning the Ed Chynoweth Cup championship in 2013 by defeating Edmonton. Wotherspoon was also named to the WHL's Western Conference second All-Star Team in 2012–13. Wotherspoon scored three points in five games at the 2013 Memorial Cup, however Portland lost the Canadian Hockey League (CHL) championship game, the Memorial Cup, to the Halifax Mooseheads, 6–4. During the season, Wotherspoon was also a member of the Canadian junior team, recording two points in six games at the 2013 World Junior Ice Hockey Championships.
 Links: a. Canadian Hockey League b. 2008–09 WHL season c. Portland Winterhawks d. Edmonton Oil Kings
Example Output: b

Example Input: Question: Did Blake or Philby defect first? Passage:In May 1986, Souther requested Soviet citizenship, aware that the investigation against him was progressing. In June, fearing imminent arrest, Souther defected to the Soviet Union by flying from the United States to Rome, where the Soviet intelligence services transferred him to Moscow. Initially, Soviet counterintelligence units were suspicious of Souther's defection and feared that he was a double agent for the CIA, but he was cleared shortly afterwards. On 2 October 1986, Souther was granted Soviet citizenship in a decree from the Presidium of the Supreme Soviet, and adopted the Russian name Mikhail Yevgenyevich Orlov. Souther was well-received by the Soviet authorities, gifting him an apartment in Moscow and a dacha on the outskirts of the city, and promoting him to the rank of major in the KGB – one of few foreign spies to be commissioned as an officer in the agency. Souther became actively engaged in scientific activities, developed his own English teaching program, walked around Moscow a lot, and travelled to other Soviet cities. Souther met and befriended other foreign Soviet intelligence agents that had defected including Kim Philby and George Blake. Souther married a Russian woman named Elena, an English teacher at the Intelligence Institute, and they had a daughter named Alexandra. In early 1989, Souther was awarded an Order of Friendship of Peoples for his contributions in the intelligence services following a petition from the KGB leadership.
 Links: a. George Blake b. George Blake c. Dacha d. Major
Example Output: a

Example Input: Question: Who is the commanding officer of the Black Watch when Evans was a second lieutenant? Passage:Following a year at Sandhurst, Evans entered the British Army with a commission in the Black Watch as second lieutenant on 23 December 1899, and served with the 2nd battalion in the Second Boer War in South Africa. He took part in operations in the Orange Free State February to May 1900, including the battles of Poplar Grove, Driefontein and Vet River; operations in the Transvaal May-June 1900, including the actions around Johannesburg, the occupation of Pretoria and the battle of Diamond Hill; and the battle of Battle of Belfast (August 1900). After the end of the conventional war he served with his battalion in the Orange River Colony during the Boer guerrilla warfare until peace was declared in June 1902. Following the end of the war in South Africa he left Point Natal for British India on the SS Ionian in October 1902 with other officers and men of his battalion, which after arrival in Bombay was stationed in Sialkot in Umballa in Punjab.. After service with his regiment in India, Evans returned to England and obtained a pilot's certificate.
 Links: a. Battle of Bergendal b. British Raj c. Orange River Colony d. Black Watch
Example Output:
d