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.

Ex Input:
Question: Where was Thomas Kenan's great grandfather born? Passage:Thomas Stephen Kenan (February 12, 1838 – December 23, 1911) was a Confederate soldier, and later a politician. His parents were Sarah Rebecca Graham and Owen Rand Kenan; he was the grandson of U.S. Congressman Thomas Kenan and great-grandson of Revolutionary War general James Kenan. He started his education in Duplin County, North Carolina at Old Grove Academy in Kenansville (the town was named for his great-grandfather in 1818). Later he spent a year at Central Military Institute in Selma, Alabama. Thomas spent his freshman year of college at Wake Forest in June. Thomas then transferred his sophomore year to the University of North Carolina, where he would graduate in 1857. He studied law for two years with Judge Pearson at Richmond Hill where he practiced law in Kenansville. After graduation and during the Civil War he became Captain of the Duplin Rifles in the Confederate States Army, elected lieutenant colonel of the 43rd North Carolina Infantry Regiment in April 1862, and was promoted to colonel later that year. He was wounded at the Battle of Gettysburg. While on an ambulance train, he and his older brother James Kenan were both captured; they were then imprisoned on Johnson's Island, Ohio. On March 22, 1865, he was released on parole but never switched sides during the war. On his return home he was elected to the state legislature from 1865 to 1867. Later that year he ran for Congress and lost. Not letting that defeat end his political career, he moved to Wilson, North Carolina, where he became mayor and was elected North Carolina Attorney General, serving from 1877 to 1885. In May 1868 he married Miss Sallie Dortch, but they had no children; Sallie died in 1916.
 Links: a. 43rd North Carolina Infantry b. American Civil War c. Owen Rand Kenan d. James Kenan

Ex Output:
d


Ex Input:
Question: Who was older, Tian Chengsi or Li Baochen? Passage:By 775, one of the military governors who had only nominally been submissive to Emperor Daizong, Tian Chengsi the military governor of Weibo Circuit (魏博, headquartered in modern Handan, Hebei), had particularly offended not only the imperial government but also his fellow warlords—by seizing much of Zhaoyi Circuit (昭義, headquartered in modern Anyang, Henan) after the death of its military governor Xue Song in 773; by looking down on Li Zhengji the military governor of Pinglu Circuit (平盧, headquartered in modern Tai'an, Shandong) and Li Baochen the military governor of Chengde (成德, headquartered in modern Shijiazhuang, Hebei); and by killing Li Baochen's brother Li Baozheng (李寶正), who was also his son-in-law, after his own son Tian Wei (田維) died after colliding with Li Baozhen while playing polo. Li Baochen and Li Zhengji thus offered to attack Tian, and Emperor Daizong decided to take this opportunity to destroy the rebellious Tian. As Zhu Tao was then submissive to the imperial government, he joined forces with Li Baochen and another general loyal to the imperial government, Xue Jianxun (薛兼訓), to attack Weibo from the north, while Li Zhengji and Li Zhongchen attacked from the south. The joint forces had initial successes, but when Zhu and Li Baochen attacked Cang Prefecture (滄州, in modern Cangzhou, Hebei), which was defended by Tian's cousin Tian Tingjie (田庭玠), they could not capture it quickly. Meanwhile, Tian Chengsi had persuaded Li Zhengji to withdraw with flattery. In addition, Li Baochen was offended when an imperial eunuch, Ma Chengqian (馬承倩), who had visited Li Baochen's army, was so dissatisfied with Li Baochen's gift to him that he threw it on the ground, and Tian was also able to use hoaxes to persuade Li Baochen that if he joined forces with Tian to attack Lulong, he would be successful. Li Baochen thus turned against Zhu, launching a surprise attack on him, but was unable to kill Zhu, effectively ending any hopes of the campaign against Tian and subsequently creating an enmity between the Chengde and Lulong Circuits. Emperor Daizong was subsequently forced to reaccept Tian Chengsi's nominal submission.
 Links: a. Tai'an b. Polo c. Shandong d. Li Baochen

Ex Output:
d


Ex Input:
Question: When did the war that Enichi-ji sent troops to Shinano start? Passage:Enichi-ji was opened in 807 by the Hossō sect scholar-monk Tokuitsu, who had come from Nara to spread the faith in the Aizu region. He overcame the followers of the Tendai and Shingon sects to become preeminent in Aizu, and by the time of his death in 842, the temples was a complete Shichidō garan with 300 monks in residence, several thousand sōhei and more than 3500 sub-temples. By the late Heian period, the temple had extended its holdings into eastern Echigo province and had established close ties with the Taira clan. During the Genpei War, the temple sent troops in support of the Heike in Shinano Province against Kiso Yoshinaka. However, the temple's leading general, Jōtan-bō, was killed at the 1181 Battle of Yokotagawa by Yoshinaka's forces, and the temple's forces withdrew and the temple went into decline.
 Links: a. Aizu b. Taira clan c. Genpei War d. Tokuitsu

Ex Output:

c