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: Which of the two who collaborated together in the Dark Knight Trilogy films is older? Passage:Michael Caine is an English actor who has appeared in over 130 films and has had multiple television appearances. Caine's acting career began in the 1950s, when he was cast in many small, often uncredited roles in British films. Caine gained recognition as one of the most famous actors of the 1960s through his breakthrough role in the film Zulu (1964). He then portrayed spy Harry Palmer in the films The Ipcress File (1965), Funeral in Berlin (1966) and Billion Dollar Brain (1967). He also had starring roles in The Italian Job and Battle of Britain (both 1969). His role in Sleuth (1972) led him to an Academy Award for Best Actor nomination. Caine has won a Best Supporting Actor Oscar for the films Hannah and Her Sisters (1986) and The Cider House Rules (1999). More recently, Caine has gained a new following through his collaborations with British-American filmmaker Christopher Nolan in the Dark Knight Trilogy films, as well as Inception (2010) and Interstellar (2014).
 Links: a. Michael Caine b. Funeral in Berlin (film) c. Christopher Nolan d. Zulu (1964 film)
Example Output: a

Example Input: Question: Which state where Peganum harmala is found is the most populous? Passage:It was first planted in the United States in 1928 in New Mexico by a farmer wanting to manufacture a dye called "Turkish red" from its seeds. From here the plant spread over most of southern New Mexico and the Big Bend region of Texas. An additional spread has occurred from east of Los Angeles in California to the tip of southernmost Nevada. Outside of these regions the distribution in the USA is not continuous and localised. As of 2019 it has been reported in southern Arizona (in at least 3 adjacent counties), northeastern Montana (2 adjacent counties), northern Nevada (Churchill county), Oregon (town of Prineville in the Oregon high desert) and possibly Washington. "Because it is so drought tolerant, African rue can displace the native saltbushes and grasses growing in the salt-desert shrub lands of the Western U.S."
 Links: a. Montana b. Churchill County, Nevada c. New Mexico d. Oregon
Example Output: c

Example Input: Question: What age was Dale Russell when the species was placed in the new genus Archaeornithomimus? Passage:In 1923, during the American Museum of Natural History expedition by Roy Chapman Andrews to Inner Mongolia, Peter Kaisen discovered numerous theropod remains in three quarries. These were named and shortly described by Charles Whitney Gilmore in 1933 as a new species of Ornithomimus: Ornithomimus asiaticus. The specific name refers to the Asian provenance. The species was placed in the new genus Archaeornithomimus by Dale Russell in 1972, making Archaeornithomimus asiaticus the type species of the genus. The generic name combines that of Ornithomimus with a Greek ἀρχαῖος (archaios), "ancient", because Russell mistakenly believed that the layers Archaeornithomimus was found in dated to the Cenomanian-Turonian, about 95 million years old, making it one of the oldest ornithomimids known at the time. Gilmore had not assigned a holotype specimen; in 1990 David Smith and Peter Galton in the first comprehensive description of the fossils, choose specimen AMNH 6565, a foot, as the lectotype.
 Links: a. American Museum of Natural History b. Holotype c. Turonian d. Dale Russell
Example Output:
d