user: 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.

Ex Input:
Question: When was Sale's first husband born? Passage:On June 21, 2012, Simpson married Canadian figure skater Jamie Salé, whom he had "known for years from the Edmonton skating scene". They had been paired as partners in late 2009 for the first season of the CBC show Battle of the Blades, which they won. Simpson and Salé have one daughter, Samantha Rae Simpson, born on July 7, 2013. Through this marriage, Simpson is also a stepfather to Salé's son Jesse Pelletier (born September 30, 2007), from her first marriage to skating partner David Pelletier. He also has three children from a previous marriage, including son Dillon, who was drafted by the Edmonton Oilers in the 4th round of the 2011 NHL Entry Draft and is currently a defenseman for the Bakersfield Condors.
 Links: a. Battle of the Blades b. David Pelletier c. Battle of the Blades (season 1) d. Stepfather

Ex Output:
b


Ex Input:
Question: How old was Kennedy when he was assassinated? Passage:1964 is a documentary film produced by Insignia Films for the American Experience series about political, social and cultural events in the United States for the calendar year 1964. It is based partly on Jon Margolis book The Last Innocent Year: America in 1964. The documentary depicts the year 1964 as significant and epic in that following the assassination of President John F. Kennedy in late 1963, 1964, as a presidential election year, becomes a departure point for American history, with lasting effects today. It is also the year of the British Invasion led by the Beatles, when Cassius Clay fights Sonny Liston for the World Heavyweight Championship, the year after Betty Friedan's book, The Feminine Mystique, is published, and the year Republican activist, Phyllis Schlafly's book, A Choice, Not an Echo, is published. It is also the year of Freedom Summer, an initiative by the Student Nonviolent Coordinating Committee to register African-Americans in Mississippi, the subsequent murders of Chaney, Goodman, and Schwerner, three CORE activists, in Mississippi by white supremacists that created a national sensation, and the Harlem riot of 1964, culminating in the Berkeley Free Speech Movement at the University of California at Berkeley. A recurrent theme of the film is its departure as a presidential election year, with President Lyndon B. Johnson running as the expected Democratic Party nominee and the nomination of U.S. Senator Barry Goldwater selected through a grassroots campaign for the Republican nomination for President of the United States, that defines the future divisions of the US political party competition.
 Links: a. British Invasion b. Harlem riot of 1964 c. Assassination of John F. Kennedy d. Muhammad Ali

Ex Output:
c


Ex Input:
Question: What year was the railroad company who held a monopoly on rate first found? Passage:By the 1920s, SCGX was doubling annually and had emerged as the "fastest growing grain market in the world"; transacting 22 million bushels in 1928 (valued at $336 million in 2018), resulting from its location in the heart of the Corn Belt and self-imposed standards before the Grain Standards Act of 1916 including species admittance and non-mixing. However, its growth was limited by shipping rates. With the trucking industry and Interstate Highway System not yet developed, SCGX was constrained by monopolized railroad rates, primarily by the Great Northern Railway. Exhausting their bargaining power with the Interstate Commerce Commission, SCGX President Charles C. Flanley directed future lobbying efforts to unlocking barge navigation of the Missouri River. His initiative was stalled throughout the 1930s by the Great Depression and Dust Bowl. In 1938, a renewed thirteen year campaign led by Secretary William Henry Marriott finally opened commercial navigation of the Missouri River and helped establish the Missouri River Basin Project, which included development of the Gavins Point Dam. The alternate transportation succeeded in breaking the railroad's monopoly. By the 1970s, SCGX was among the largest exchanges in the world; transacting over 100 million bushels annually (valued at $1 billion as of 2018).
 Links: a. Interstate Highway System b. Sanford House (Sioux City, Iowa) c. History of the trucking industry in the United States d. Great Northern Railway (U.S.)

Ex Output:


assistant: d