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 long had the Royal Canadian Air Force existed the year that the McDonnell CF-101 Voodoo began being operated by them? Passage:The McDonnell CF-101 Voodoo was an all-weather interceptor aircraft operated by the Royal Canadian Air Force and the Canadian Forces between 1961 and 1984. They were manufactured by the McDonnell Aircraft Corporation of St. Louis, Missouri for the United States Air Force (as F-101s), and later sold to Canada. CF-101s replaced the obsolete Avro CF-100 Canuck in the RCAF's all-weather fighter squadrons. The Voodoo's primary armament was nuclear AIR-2A Genie unguided air-to-air rockets, and there was significant political controversy in Canada about their adoption. Although they never fired a weapon in wartime, the CF-101 served as Canada's primary means of air defence from Quick Reaction Alert facilities at Canadian airbases. The CF-101s were retired in the 1980s and replaced with McDonnell Douglas CF-18 Hornet fighters. Many examples are preserved in museums and parks in Canada and the United States.
 Links: a. AIR-2 Genie b. Royal Canadian Air Force c. McDonnell Douglas CF-18 Hornet d. Royal Canadian Air Force
Example Output: b

Example Input: Question: How old was Beloff's husband when he died? Passage:Anne Beloff was born in 1921 in Hampstead to Simon Beloff and Marie Katzin. Her parents were of Russian–Jewish background, and her siblings included the historian Max Beloff, Baron Beloff, the psychologist John Beloff, the journalist Nora Beloff, and the politician Renee Soskin. She earned a degree in chemistry from University College London in 1942 before completing a PhD in the biochemistry of skin burns with Rudolph Peters at the University of Oxford. She visited Harvard Medical School in 1946 to perform research and returned to the UK in 1948. In the same year she married Ernst Boris Chain, a biochemist who had won the Nobel Prize in Physiology or Medicine in 1945, and moved with him to Rome.
 Links: a. Harvard Medical School b. Ernst Chain c. University of Oxford d. Hampstead
Example Output: b

Example Input: Question: In what state did Lisa Lisa appear at the eighth annual Forever Freestyle showcase? Passage:Lisa Lisa released a solo album called LL77 in 1994, which included the moderate club hit "When I Fell In Love" (which was remixed by Junior Vasquez) and the notable single "Skip to My Lu", which hit No. 38 on the R&B chart. She resurfaced circa 2001 on the Nickelodeon series Taina, in which she played the title character's mother. On June 24, 2008, Lisa Lisa presented an award at the BET Awards sparking interest that she may be plotting a comeback. In 2009, she released Life 'n Love, a full-length album of new material on Mass Appeal Entertainment featuring the single "Can't Wait" with guest rapper Pitbull. The album also features a cover version of the song "Stand" which was originally performed by Taylor Dayne on her 1998 album Naked without You. In March 2014, she appeared with Stevie B., TKA, Sa-Fire, and others at the eighth annual Forever Freestyle showcase at the Lehman College Center for the Performing Arts in the Bronx.
 Links: a. Nickelodeon b. Naked Without You (album) c. Lehman College d. Nickelodeon
Example Output:
c