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.

Input: Consider Input: Question: How old was Ibrahim Pasha the year the conquest of the Sudan began? Passage:The reign of Farouk was characterized by ever increasing nationalist discontent over the British occupation, royal corruption and incompetence, and the disastrous 1948 Arab–Israeli War. All these factors served to terminally undermine Farouk's position and paved the way for the revolution of 1952. Farouk was forced to abdicate in favor of his infant son Ahmed-Fuad who became King Fuad II, while administration of the country passed to the Free Officers Movement under Muhammad Naguib and Gamal Abdel Nasser. The infant king's reign lasted less than a year and on June 18, 1953, the revolutionaries abolished the monarchy and declared Egypt a republic, ending a century and a half of the Muhammad Ali Dynasty's rule. Emerging victorious from a war-triangle (Ottomans, Mamluks, and his loyal troops), Mehmed Ali made good use of Albanian irregulars services as mercenaries and troops to bolster his reign. Albanian mercenaries, or Arnauts, presented the backbone of Ali's army and were known as elite and undisciplined soldiers of the Ottoman Empire armies. With the rise of Muhammad Ali in power, many of them would settle in Egypt and serve there. By 1815, the number of Albanian military was over 7000. Albanian troops partook in the war against the Wahhabi movement in Arabia (1811–18) and in the conquest of the Sudan (1820–24). The number of Albanian troops would diminish in 1823, when Ibrahim Pasha, Ali's son, would join the Ottoman armies in the Greek War of Independence along with circa 17,000 men, many of them Albanians. Ali's dynasty would continue to rule Egypt until 1952.
 Links: a. Free Officers Movement (Egypt) b. Egyptian revolution of 1952 c. Ibrahim Pasha of Egypt d. Free Officers Movement (Egypt)

Output: c


Input: Consider Input: Question: When was the author of JFK and the Unspeakable born? Passage:Jim Garrison said anti-Communist and anti-Castro extremists in the CIA plotted the assassination of Kennedy to maintain tension with the Soviet Union and Cuba, and to prevent a United States withdrawal from Vietnam. James Douglass wrote in JFK and the Unspeakable that the CIA, acting upon the orders of conspirators with the "military industrial complex", killed Kennedy and in the process set up Lee Harvey Oswald as a patsy. Like Garrison, Douglass stated that Kennedy was killed because he was turning away from the Cold War and pursuing paths of nuclear disarmament, rapprochement with Fidel Castro, and withdrawal from the war in Vietnam. Mark Lane — author of Rush to Judgment and Plausible Denial and the attorney who defended Liberty Lobby against a defamation suit brought by former CIA agent E. Howard Hunt — has been described as a leading proponent of the theory that the CIA was responsible for the assassination of Kennedy. Others who believe the CIA was involved include authors Anthony Summers and John M. Newman.
 Links: a. Vietnam War b. Vietnam War c. James W. Douglass d. Lee Harvey Oswald

Output: c


Input: Consider Input: Question: When did the US enter the war that McNamara fought in as a sergeant of the 87th Division? Passage:McNamara was a native of Fair Haven, Vermont, and attended the schools of Fair Haven. He graduated from College of the Holy Cross in 1915, studied law with a Vermont attorney, and attended Harvard Law School. Leaving law school early to enter the military for World War I, McNamara served in the United States Army and attained the rank of sergeant as a member of the 87th Division. After leaving the Army, McNamara was admitted to the bar and began to practice law in Burlington, Vermont. He became active in politics as a Democrat, and served as Burlington's municipal court judge from 1921 to 1923. After unsuccessful runs for Vermont Attorney General and the U.S. House, in 1933 McNamara was named US Attorney for Vermont. He held the post through the administrations of Democrats Franklin Roosevelt and Harry Truman, and resigned after Republican Dwight Eisenhower became president.
 Links: a. Dwight D. Eisenhower b. World War I c. Burlington, Vermont d. Harry S. Truman


Output: b