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 was the event where Norton made his first of four combat jumps as an executive officer? Passage:Norton's first assignment out of West Point was to 12th Infantry Regiment, 4th Infantry Division as a company commander. He then returned to Infantry School in the fall of 1942 to attend the Battalion Commander and Staff Officers Course and the Parachute Course. Following his completion of the course, he reported to the 82nd Airborne Division in North Africa. He was soon promoted to executive officer of the 2d Battalion, 505th Parachute Infantry Regiment. Two months later, he was again promoted, to S-3 (operations officer) of the Regiment. He made his first of four combat jumps as an executive officer, participating in the Invasion of Sicily. After returning to North Africa, he made a second combat jump into Salerno, Italy, blocking German forces who were trying to attack US amphibious forces. His third jump was in support of the Invasion of Normandy on D-Day, 6 June 1944. In July of that year, he assumed command of the 3d Battalion; he was promoted the next month to G3 of the 82d Airborne Division. Norton made his fourth combat jump in September, in the Netherlands to take control of the bridges from the Dutch border to Arnhem as part of Operation Market Garden.
 Links: a. 82nd Airborne Division b. Operation Market Garden c. Netherlands d. Allied invasion of Sicily
Example Output: d

Example Input: Question: How many years after the Clairvaux was found, was the Margam Abbey founded? Passage:The abbey was founded in 1147 as a daughter house of Clairvaux by Robert, Earl of Gloucester, and was dedicated to the Blessed Virgin Mary. Early Christian crosses found in the close vicinity and conserved in the nearby Margam Stones Museum suggest the existence of an earlier Celtic monastic community. The founding abbot was William of Clairvaux. The third abbot, Conan, enjoyed the praise of Giraldus Cambrensis, whom he appears to have entertained prior to his official visit with Baldwin of Forde, Archbishop of Canterbury, to preach the Crusade in 1188. Conan (or Cunan) contributed to Patristic literature, as he is credited with the capitula or chapter-headings prefixing each section of St. Bernard's Sermons on the Song of Songs, one of the works for which that author was titled a Doctor of the Church.
 Links: a. Clairvaux Abbey b. Clairvaux Abbey c. Pilcrow d. Pilcrow
Example Output: a

Example Input: Question: Who was the first person to hold the position Theodore Sorensen was nominated for? Passage:In the 1976 Republican primary, President Ford faced a challenge from former California Governor Ronald Reagan, who selected Richard Schweiker as his running mate. Though Thurmond backed Reagan's candidacy, he, along with North Carolina Senator Jesse Helms, led efforts to oust Schweiker from the ticket. During the subsequent general election, Thurmond appeared in a campaign commercial for incumbent U.S. President Gerald Ford in his race against Thurmond's fellow Southerner, former Georgia Governor Jimmy Carter. In the commercial, Thurmond said Ford (who was born in Nebraska and spent most of his life in Michigan) "sound[ed] more like a Southerner than Jimmy Carter". After President-elect Carter nominated Theodore C. Sorensen as his choice to become Director of the Central Intelligence Agency, Thurmond expressed reservations and fellow Senator Jake Garn said he believed Thurmond would not vote for the nomination. Sorensen withdrew from consideration days later, before a vote could be had.
 Links: a. Jesse Helms b. Director of the Central Intelligence Agency c. Ted Sorensen d. Politics of the Southern United States
Example Output:
b