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 President's children have lived in the White House? Passage:Within weeks, many Americans could recite favorite lines from the record, including "the rubber schwan [swan] is mine", and "move ahead...with great vigah [vigor]", the latter lampooning the President's own words. The album poked fun at Kennedy's PT-109 history; the rocking chairs he used for his painful back; the Kennedy clan's well-known athleticism, football games and family togetherness; children in the White House; and Jackie Kennedy's soft-spoken nature and her redecoration of the White House; and many other bits of knowledge that the public was eager to consume. Kennedy himself was said to have given copies of the albums as Christmas gifts, and once greeted a Democratic National Committee group by saying, "Vaughn Meader was busy tonight, so I came myself." According to UPI reporter Merriman Smith, during a Cabinet meeting Kennedy played the entire record for everyone. At one press conference, Kennedy was asked if the album had produced "annoyment (sic) or enjoyment." He jokingly responded, "I listened to Mr. Meader's record and, frankly, I thought it sounded more like Teddy than it did me. So, now he's annoyed."
 Links: a. Child b. Rocking chair c. Sport d. Ted Kennedy
Example Output: a

Example Input: Question: How deep were their heavy infantry formations normally? Passage:Having recovered from their losses at Trebia (218 BC) and Lake Trasimene (217 BC), the Romans decided to engage Hannibal at Cannae, with approximately 86,000 Roman and allied troops. They massed their heavy infantry in a deeper formation than usual, while Hannibal used the double envelopment tactic and surrounded his enemy, trapping the majority of the Roman army, who were then slaughtered. The loss of life on the Roman side was one of the most lethal single day's fighting in history; Adrian Goldsworthy equates the death toll at Cannae to "the massed slaughter of the British Army on the first day of the Somme offensive in 1916." Only about 15,000 Romans, most of whom were from the garrisons of the camps and had not taken part in the battle, escaped death. Following the defeat, Capua and several other Italian city-states defected from the Roman Republic to Carthage.
 Links: a. Cannae b. Adrian Goldsworthy c. Heavy infantry d. City-state
Example Output: c

Example Input: Question: How many songs were on the full-length debut album? Passage:Crime in Stereo formed in 2001 and recorded a homemade demo tape that same year. The band released their debut, a split with New York City's Kill Your Idols, in 2003 on Blackout! Records. In early 2004, the band released their debut full-length in conjunction with Brightside Records, Explosives and the Will to Use Them and was well received by several punk music webzines. In early 2005 the band signed with Nitro Records, owned by Dexter Holland of The Offspring. Although a four-song EP titled The Contract was released in July 2005 to finish up the band's contract with Blackout! Records / Brightside, the band released the Fuel. Transit. Sleep EP that same year with Nitro Records containing two songs from the following album, The Troubled Stateside, which was released April 18, 2006 on Nitro Records.
 Links: a. Explosives and the Will to Use Them b. Nitro Records c. Nitro Records d. Nitro Records
Example Output:
a