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.

[Q]: Question: How long did the state entity that  Macedonia was the political heart of  last? Passage:In 1014, after decades of war, the Byzantine Emperor Basil II scored a decisive victory over the Bulgarian Emperor Samuil in the battle of Kleidion. Samuil died of a heart attack on 6 October 1014 and the Byzantines took the opportunity to penetrate deep into Macedonia, the political heart of the Bulgarian Empire, and seized a number of important cities (Bitola, Prilep, Voden, Maglen). After the new Bulgarian Emperor Ivan Vladislav, who in 1015 assassinated Samuil's son and heir Gavril Radomir, had unsuccessfully tried to make an agreement with Basil II, he organized the defense of the country. The Bulgarians led by the Emperor, Krakra of Pernik and Ivats managed to return a number of towns and castles. The Byzantines were defeated in the battle of Bitola (September 1015) and at the siege of Pernik (summer of 1016).
 Links: a. Basil II b. Ivan Vladislav of Bulgaria c. First Bulgarian Empire d. Prilep
[A]: c


[Q]: Question: How old was Rudy Vallee when he reached number 15 on the Billboard charts? Passage:Rudy Vallee was the first artist to make the charts in Billboard magazine with "As Time Goes By" when he took the song to number 15 in 1931, but after the song was featured in the film Casablanca his recording was reissued and spent four weeks at number one in 1943. "Begin the Beguine" was first put on the charts by Xavier Cugat & His Waldorf-Astoria Orchestra with Don Reid on vocal for two weeks in 1935 when it reached number 13. Patti Austin's "We're in Love" made it to number 90 on the magazine's R&B chart in February 1978, and the Expanded Edition CD bonus track "I Never Said I Love You" was first recorded by Barbara Mandrell for her 1976 album Midnight Angel but was a number 84 pop hit for Orsa Lia that also spent a week at number one on the magazine's Easy Listening chart in 1979.
 Links: a. Waldorf Astoria New York b. Casablanca (film) c. Barbara Mandrell d. Rudy Vallée
[A]: d


[Q]: Question: How is Yale University's Sheffield Scientific School named after? Passage:Following the war, Walker served on the editorial staff of the Springfield Republican before using his family and military connections to gain appointment as the Chief of the Bureau of Statistics from 1869 to 1870 and Superintendent of the 1870 census where he published an award-winning Statistical Atlas visualizing the data for the first time. He joined Yale University's Sheffield Scientific School as a professor of political economy in 1872 and rose to international prominence serving as a chief member of the 1876 Philadelphia Exposition, American representative to the 1878 International Monetary Conference, President of the American Statistical Association in 1882, and inaugural President of the American Economic Association in 1886, and vice president of the National Academy of Sciences in 1890. Walker also led the 1880 census which resulted in a twenty-two volume census, cementing Walker's reputation as the nation's preeminent statistician.
 Links: a. Political economy b. Sheffield Scientific School c. Political economy d. 1870 United States Census
[A]:
b