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: Of the two players who each scored first for Brazil and Chile, whose birthday falls earlier in the year? Passage:Brazil faced Chile in the round of 16, taking an 18th-minute lead through David Luiz's first goal for the Seleção. With no further scoring after Alexis Sánchez's equaliser, the match went to a penalty shootout. Brazil prevailed 3–2, with Neymar, David Luiz and Marcelo converting their kicks, and goalkeeper Júlio César saving from Chileans Sánchez and Mauricio Pinilla. The team again faced South American opposition in the quarter-final, defeating Colombia 2–1 with goals from central defenders David Luiz and team captain Thiago Silva. Late in the match, Neymar was substituted on a stretcher after Camilo Zúñiga's knee had made contact with the forward's back. Neymar was taken to hospital and later diagnosed with a fractured vertebra, which ruled him out for the remainder of the tournament. Prior to this, Neymar had scored four goals, provided one assist and been named man of the match twice. Brazil faced further problems ahead of their semi-final against Germany, as Thiago Silva was to serve a one-match suspension for receiving his second yellow card of the tournament in the quarter-final. The Seleção went on to lose 1–7 to the Germans, their biggest ever defeat at the World Cup and first home loss in a competitive match since 1975. Towards the end of the match, the home crowd began to "olé" each pass from the German team, and booed their own players off the pitch after the final whistle. The match has been nicknamed the Mineirazo, making reference to the nation's previous World Cup defeat on home soil, the Maracanazo against Uruguay in 1950, and the Estádio do Mineirão in Belo Horizonte where the match took place.
 Links: a. Brazil v Germany (2014 FIFA World Cup) b. 2014 FIFA World Cup knockout stage c. 2014 FIFA World Cup knockout stage d. David Luiz
Example Output: d

Example Input: Question: How many casualties had the Japanese Army suffered by the time Vincent was sent to Tokyo? Passage:Born the son of Colonel Arthur Hare Vincent and Elizabeth Rose Manson and educated at Wellington College and the Royal Military Academy, Woolwich, Vincent was commissioned into the Royal Artillery as a second lieutenant on 24 July 1891. He was promoted to lieutenant on 24 July 1894 and to captain on 13 February 1900. He served with the China Expeditionary Force in late 1900 and then in the Second Boer War in South Africa. Following the end of the war, Vincent left Point Natal for India on the SS Ionian in October 1902 with other officers and men of the J Battery Royal Horse Artillery, and after arrival in Bombay, was stationed in Meerut, Bengal Presidency. In 1903, Vincent was sent to Tokyo to learn Japanese: he served as British military attaché with the Japanese Army during the Russo-Japanese War and, from 1 March 1904, was attached to the 2nd Division of the First Japanese Army in Manchuria.
 Links: a. Imperial Japanese Army b. Second lieutenant c. Second Boer War d. Royal Military Academy, Woolwich
Example Output: a

Example Input: Question: What is the age difference between Byzantine Emperor and his father-in-law? Passage:With the ascendance of Simeon I to the throne in 893, the long-lasting peace with the Byzantine Empire established by his father was about to end. A conflict arose when Byzantine Emperor Leo VI the Wise, acting under pressure from his wife Zoe Zaoutzaina and her father, Stylianos Zaoutzes, moved the marketplace for Bulgarian goods from Constantinople to Thessaloniki, where Bulgarian merchants were heavily taxed. Forced to take action, in the autumn of 894 Simeon invaded the Byzantine Empire from the north, meeting little opposition due to the concentration of most Byzantine forces in eastern Anatolia to counter Arab invasions. Informed of the Bulgarian offensive, the surprised Leo sent an army consisting of guardsmen and other military units from the capital to halt Simeon, but his troops were routed somewhere in the theme of Macedonia.The Magyars managed to defeat Simeon's army twice, but in 896 they were routed in the Battle of Southern Buh. The war ended in 896 with a great Bulgarian victory near Bulgarophygon in Eastern Thrace. The market was returned to Constantinople, and the Byzantine Emperor had to pay annual tribute to Bulgaria. More importantly, with help from the Pechenegs Simeon successfully fended off a Magyar invasion, which was coordinated with the Byzantines.
 Links: a. Leo VI the Wise b. Leo VI the Wise c. Battle of Boulgarophygon d. Battle of Southern Buh
Example Output:
a