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: What was the original name of the Służba Bezpieczeństwa? Passage:On 30 June 1943 he was arrested by the Gestapo in Warsaw and sent to Berlin. Rowecki was arrested due to his betrayal by Ludwik Kalkstein "Hanka", Eugeniusz Swierczewski "Genes" and Blanka Kaczorowska "Sroka" who were Gestapo agents. All of them were members of the Home Army but in fact collaborated with the Gestapo. Swierczewski, Kalkstein and Kaczorowska were sentenced to death for high treason by the Secret War Tribunal of the Polish Secret State. The sentence on Eugeniusz Swierczewski was carried out by troops commanded by Stefan Rys ("Jozef"). They hanged Swierczewski in the basement of the house at 74 Krochmalna Street in Warsaw. Kalkstein received protection from the Gestapo and was not harmed. He fought in a Waffen SS unit during the Warsaw Uprising of 1944 under the name of Konrad Stark. After the war, he worked for the Polish Radio station in Szczecin and was later recruited as an agent by the Urząd Bezpieczeństwa. In 1982, he emigrated to France; he died in 1994. Blanka Kaczorowska also survived the war. Her death sentence was not carried out because she was pregnant. After the war, she also worked as a secret agent for the Urząd Bezpieczeństwa and later for the renamed Służba Bezpieczeństwa. She emigrated to France in 1971. She died in 2002
 Links: a. Home Army b. Ludwik Kalkstein c. Służba Bezpieczeństwa d. Warsaw Uprising

Output: c


Input: Consider Input: Question: Who was the second top scorer during the 1955-56 Serie A? Passage:Throughout his club career, Pivatelli most notably played for A.C. Milan (1961–63); he also played for Hellas Verona F.C. (1950–53), Bologna F.C. 1909 (1953–60), and S.S.C. Napoli (1960–61). After being dropped from the Inter Youth Side, Pivatelli was acquired by Verona in 1950, with whom he made his Serie B debut at the age of 17, scoring his first professional goal in his second appearance with the club, in a 4–1 victory over Vicenza. The following season, he was promoted to the starting line-up, and scored a total of 25 goals in 68 games for his team during the next three seasons, also helping the struggling club avoid relegation. After joining Bologna in 1953, he made his Serie A debut with the club on 13 September 1953, in a 2–1 home win over Atalanta. With the Emilian side, he was the Serie A top-scorer during the 1955–56 Serie A season, with 29 league goals in 30 appearances, and was the only Italian player to win the Capocannoniere title during the 1950s. In total, he scored 105 goals for Bologna during his seven seasons with the club. After playing with Napoli for the 1960–61 season, he joined Milan in 1961, and was part of the side that won the Serie A title in 1962, and the European Cup in 1963 under manager Nereo Rocco, after which he subsequently retired from playing professional football.
 Links: a. UEFA Champions League b. Capocannoniere c. S.S.C. Napoli d. 1955–56 Serie A

Output: b


Input: Consider Input: Question: In what country is the Nikos Kazantzakis Stadium located? Passage:The «Nikos Kazantzakis» Stadium (), formerly known as Ergotelis Stadium and more commonly as Martinengo Stadium, is a football stadium located on the Martinengo bastion, part of the fortifications of Heraklion, on the island of Crete. It is named after Modern Greek literature giant Nikos Kazantzakis, whose grave is also located on the same bastion. It is part of the Ergotelis Athletic Centre, a sport facilities complex owned by Greek multi-sport club Ergotelis. Built in 1946, as Ergotelis Stadium (), it was the traditional home ground of Greek football club Ergotelis until 2004, when the club moved to the Pankritio Stadium, Heraklion's largest and most modern sports venue. The complex currently houses the Ergotelis Youth Academy, the largest youth sports academy on the island of Crete, and one of the largest in Greece, while the stadium itself is still used as the home ground of multiple Heraklion football clubs playing in the Heraklion Football Clubs Association amateur league system. It has a capacity of about 1,000 spectators, of which approximately 600 can be seated.
 Links: a. Crete b. Stadium c. Heraklion d. Crete


Output: a