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 episode with Malohkeh had the highest ratings? Passage:Chibnall suggested including a "bonkers" gang of characters picked from around time and space. He felt that Doctor Who could have "collisions of characters that no other show in the world can do", and that it was about finding a "disparate" group of characters who would "bounce" off each other. Nefertiti's decision not to return to her own time fits in with the historical record, as the date and cause of her death are unknown. Chibnall asked to introduce Rory's father, as Amy and Rory would be leaving in four episodes and Rory's family life had not been explored yet. Mark Williams who played Rory's father previously appeared in the Fifth Doctor audio adventure The Eternal Summer. Rupert Graves, who played an Edwardian hunter in this episode, previously worked with Moffat on the BBC series Sherlock. David Bradley's character, Solomon, was modelled on a "well-known nightclub owner with long hair". Chibnall described him as "half businessman, half Somali pirate". Bradley and Williams had previously worked together on the Harry Potter film franchise. Bradley was later cast as the First Doctor William Hartnell for the 50th anniversary documentary drama An Adventure in Space and Time. Comedy duo Mitchell and Webb provided the voices of Solomon's two robots; executive producer Caroline Skinner called the casting choice "perfect". Richard Hope, who played the Silurian Bleytal, previously appeared as Malohkeh in the episodes "The Hungry Earth", "Cold Blood" and "The Wedding of River Song".
Links: a. Richard Hope (actor) b. The Hungry Earth c. Mitchell and Webb d. Harry Potter (film series)
Example Output: b

Example Input: Question: Who was the editor of the Daily Express the year Morris traveled to the West Indies? Passage:Leaving Collurian he worked as a porter at Penzance railway station for the Great Western Railway and with the free pass, that was part of his entitlement, he travelled to London to search for a post as a journalist. He landed his first job with The Dairy Farmer and later Farmers Weekly. He travelled to the West Indies in 1939 and Canada where he joined the Canadian Army at the outbreak of World War II, but was invalided out in 1941. Back in Britain, he started as a sub-editor on the Daily Express, and later as a personal assistant to Manny Shinwell, a Labour MP, writing speeches for members of the party. In 1949 he became political columnist for the Daily Mirror, and unsuccessfully standing as a Labour party candidate for Bristol West in 1950 and 1951.
Links: a. Canadian Army b. World War II c. Daily Mirror d. Daily Express
Example Output: d

Example Input: Question: What other types of fossils have been found in the Villaieja Formation? Passage:Anachlysictis gracilis is an extinct carnivorous mammal belonging to the group Sparassodonta, which were metatherians (a group including marsupials and their close relatives) that inhabited South America during the Cenozoic. Unlike other remains assigned to the family Thylacosmilidae (a group of metatherian predators equipped with "saber teeth") that had been found previously, Anachlysictis is the first record of such borhyaenoids in northern South America, and also most primitive and ancient in the family (in fact, is the first confirmed record that did not belong to the genus Thylacosmilus, until the official publication of Patagosmilus in 2010). This species was found in the Villavieja Formation in the area of La Venta in Colombia, a famous fossil deposit in the Middle Miocene (Laventan; 13.8-11.8 million years ago), based on fragments that include a front portion of the lower jaw, with an incipient molar tooth and a piece of carnassial from the front of the maxilla.
Links: a. Miocene b. Honda Group, Colombia c. La Venta (Colombia) d. South America
Example Output:
b