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: Of the two colonies captured by Philip, which one was established first? Passage:Athens and Macedon had been at war since 356 BC, after Philip's capture of the Athenian colonies of Pydna and Potidea. Shortly afterwards, the Third Sacred War began after the Phocian seizure of the Temple of Apollo in Delphi. Athens allied herself with Phocis, against the other members of the Amphictyonic League. In 354 or 353 BCE, the Thessalians, having been defeated by the Phocians, requested that Philip become archon of Thessaly, to which Philip assented, drawing Macedon into the Sacred War. In 352 BC, Philip's erstwhile ally, the Chalkidian League (led by Olynthos), alarmed by Philip's growing power, sought to ally themselves with Athens, in clear breach of their alliance with Philip. In response, Philip attacked Chalkidiki in 349 BC, and by 348 BC, had completely destroyed the Chalkidian League, razing Olynthos in the process.
 Links: a. Phocis (ancient region) b. Chalcidian League c. Expansion of Macedonia under Philip II d. Pydna
Example Output: d

Example Input: Question: How many Grammy awards did the singer who re-recorded the song written by Sam Dees win? Passage:In 1983, The Manhattans released the album Forever by Your Side, by Columbia Records, which brought the two singles the group that year. The first was the song "Crazy", the great success of this album, peaked at number 4 on the R&B chart. The second single was the title track "Forever by Your Side", which had moderate success in the United States, peaked at number 30 on the R&B chart, but has become a great success and a romantic classic in Brazil two years later, when it was included as part of the soundtrack of a soap opera in the country in 1985. The success led to a Portuguese version the following year, called "Pra Sempre Vou Te Amar", which also was successful in Brazil, and has been recorded by several Brazilian artists. Another highlight of this album Forever by Your Side was the song "Just The Lonely Talking Again", written by the American singer and songwriter Sam Dees, which was originally recorded by The Manhattans this 1983 album and was later re-recorded by Whitney Houston on her second studio album "Whitney" in 1987.
 Links: a. Soap opera b. Whitney (album) c. Brazil d. Whitney Houston
Example Output: d

Example Input: Question: Of the three rivers the 90th Infantry Division crossed together, which is the widest? Passage:After a short rest, the 90th continued across the Moselle River to take Mainz, 22 March, and crossed the rivers Rhine, the Main, and the Werra in rapid succession. Pursuit continued to the Czech border, 18 April 1945, and into the Sudetes mountain range. The division was en route to Prague when they came upon the remaining 1500 emaciated prisoners left behind by the SS at Flossenbürg concentration camp. Today, a memorial wall at the former camp honors the 90th as the liberators of Flossenbürg concentration camp. A week later, word came that the war in Europe ended on 8 May 1945. On that same day, Erich Hartmann, the highest-scoring fighter ace in history, along with a squadron of the elite Jagdgeschwader 52 fighter wing (the highest-scoring fighter wing in history), surrendered to the 90th.
 Links: a. Mainz b. Prague c. Rhine d. Rhine
Example Output:
c