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.

Question: How long had Juan Carlos Onganía been leading Argentina by the year La balsa was written? Passage:"La balsa" (; Spanish for "the raft") is the debut single by the Argentine band Los Gatos, released on July 3, 1967 on Vik, a subsidiary of RCA Victor. Formed in 1967 after the disbandment of Los Gatos Salvajes, Los Gatos were the house band of the bar La Cueva, which became a popular meeting place for rock enthusiasts and the birthplace of Argentine rock—known locally as rock nacional (Spanish for "national rock"). During the mid-to-late 1960s, Buenos Aires was experiencing a cultural blossoming characterized by innovations in modern art, literature and cinema, largely driven by a burgeoning youth subculture that adhered to the countercultural phenomenon of the decade. The underground had its center in La Cueva, Plaza Francia and the Torcuato di Tella Institute, and identified with British Invasion music and the sexual revolution. "La balsa" was written by Litto Nebbia—lead vocalist of the band—and Tanguito (credited as Ramsés) on May 2, 1967, in the men's toilet of La Perla de Once, another bar frequented by the group. At the time, Argentina was under a military dictatorship led by Juan Carlos Onganía, which regularly imprisoned and persecuted these young bohemians.
 Links: a. British Invasion b. Juan Carlos Onganía c. Argentine rock d. Tanguito
b

Question: Do more than 10,000 people live in the city where Bonnaroo is held? Passage:After the release of Levitate, his first full-length album, in 2011, he began to play shows and festivals around the country. Starting in 2012 with a US tour that saw him hit the road with The M Machine, he continued on to play the Coachella Valley Music and Arts Festival, more commonly known as Coachella, a festival that takes place in April in Indio, California. After Coachella he played Electric Forest Festival in Rothbury, Michigan in June 2012. He then played Lollapalooza Music Festival in Chicago, Illinois Grant Park (Chicago) in early August 2012 before Heading to New York City to play Electric Zoo Festival at the end of August 2012 on Randall's Island. He then kicked off his very own solo Night Vision Tour 2012 in September by releasing a 30-minute mix entitled Night Vision Tour Mix 2012. He has also played at Bonnaroo Music Festival in June 2013 in Manchester, Tennessee.
 Links: a. Coachella Valley Music and Arts Festival b. New York City c. Manchester, Tennessee d. The M Machine
c

Question: How many years was the Pinus strobus seen on the state flag of Maine? Passage:In the United States it is the State Tree of Maine (as of 1945) and Michigan (as of 1955). Its "pine cone and tassel" is also the State Flower of Maine. Sprigs of eastern white pine were worn as badges as a symbol of Vermont identity during the Vermont Republic and are depicted in a stained glass window in the Vermont State House, on the Flag of Vermont, and on the naval ensign of the Commonwealth of Massachusetts and the state of Maine. The 1901 Maine Flag prominently featured the tree during its brief tenure as Maine's state flag. The Maine State Guard also use the tree in their uniform badges.
 Links: a. Maine State Guard b. Vermont c. Flag of Maine (1901–09) d. List of U.S. state and territory flowers

c