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 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
Example Output: c

Example Input: Question: How old was Norimasa kaeriyama when he directed The Glow of Life? Passage:Among intellectuals, critiques of Japanese cinema grew in the 1910s and eventually developed into a movement that transformed Japanese film. Film criticism began with early film magazines such as Katsudō shashinkai (begun in 1909) and a full-length book written by Yasunosuke Gonda in 1914, but many early film critics often focused on chastising the work of studios like Nikkatsu and Tenkatsu for being too theatrical (using, for instance, elements from kabuki and shinpa such as onnagata) and for not utilizing what were considered more cinematic techniques to tell stories, instead relying on benshi. In what was later named the Pure Film Movement, writers in magazines such as Kinema Record called for a broader use of such cinematic techniques. Some of these critics, such as Norimasa Kaeriyama, went on to put their ideas into practice by directing such films as The Glow of Life (1918), which was one of the first films to use actresses (in this case, Harumi Hanayagi). There were parallel efforts elsewhere in the film industry. In his 1917 film The Captain's Daughter, Masao Inoue started using techniques new to the silent film era, such as the close-up and cut back. The Pure Film Movement was central in the development of the gendaigeki and scriptwriting.
 Links: a. Pure Film Movement b. Kabuki c. Norimasa Kaeriyama d. The Glow of Life
Example Output: c

Example Input: Question: Who directed Calhern in his role as the devious George Caswell? Passage:In 1923, Calhern left the movies, deciding to devote his career entirely to the stage, but he would later return to the screen after the advent of sound pictures. In films, He was primarily cast as a character actor, while he continued to play leading roles on the stage. He reached his peak in the early 1950s as a Metro-Goldwyn-Mayer contract player. Among Calhern's many memorable screen portrayals were Ambassador Trentino in the Marx Brothers classic Duck Soup (1933) and three diverse roles that he appeared in at MGM in 1950: a singing role as Buffalo Bill in the film version of the musical Annie Get Your Gun, as a double-crossing lawyer and sugar-daddy to Marilyn Monroe in John Huston's film noir classic The Asphalt Jungle, and his Oscar-nominated performance as Oliver Wendell Holmes in The Magnificent Yankee (re-creating his role from the Broadway stage). He was also praised for his portrayal of the title role in the John Houseman production of Julius Caesar (adapted from the Shakespeare play) in 1953, directed by Joseph L. Mankiewicz. Calhern also played the role of the devious George Caswell, the manipulative board member of Tredway Corporation in the 1954 production of Executive Suite.
 Links: a. Annie Get Your Gun (film) b. Buffalo Bill c. Joseph L. Mankiewicz d. Executive Suite
Example Output:
d