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: Who was older during their time at Sports Fan Radio Network, Pete Rose or Pat O'Brian? Passage:By 1994, SportsFan expanded to a 24/7 format, seven days a week. The signature show, SportsFan Tonight moved its broadcast location from the MGM Grand Las Vegas in 1994. Later it moved to the sportsbook at the Mandalay Bay. The daily line up included baseball's all-time hit leader Pete Rose, as well as a stable of young talent. Others hosting shows over the years included former NFL QB Sean Salisbury, former NFL All-Pro Tim Ryan, Fox and CBS host James Brown, longtime broadcaster Pat O'Brien, former NBA coach Matt Goukas, NHL great Phil Esposito, former NFL All-Pro Bob Golic and former NCAA basketball coaches Bill Frieder and Fran Fraschilla. Other hosts included Bruce Schein, Chris Russo (now Russell), J. T. the Brick, Steve Cofield, Rob Tepper, Chuck Powell, Ryan Williams,Marty Tirrell, Ken Miller, Soren Petro, Rob Fischer, Mike "The Sports Pig" Responts, John Phillips, John Rabe, Brandon Tierney, Jim Brinson, Chad Andrus. Scott Ferrall, Dave Cokin, Eric Pollero, Tim Neverett and others. By the late '90s, SportsFan partnered with CBS Sportsline to broadcast two shows daily. One program was hosted by Craig Carton, the other "The Drive" with Scott Kaplan and Sid Rosenberg. Later they landed a handful of other significant names, including Nanci Donellan (a.k.a. "The Fabulous Sports Babe") from ESPN Radio. Keith Olbermann also hosted a few shows.
 Links: a. Phil Esposito b. Sean Salisbury c. Pete Rose d. Keith Olbermann
Example Output: c

Example Input: Question: How old was the winner of the 18th season of Celebrity Big Brother when they won? Passage:The third series of the show began on 11 August 2015. The official list of cast members was released on 14 July 2015. This series was filmed in Cancun, Mexico, making this the first series to be filmed outside of Europe. They include four boys: Graham Griffiths, Jayden Robins, Kirk Norcross and Stephen Bear, and four girls: Amy Paige Cooke, Laura Alicia Summers, Megan McKenna and Megan Rees. With the announcement of the line-up it was confirmed that former Geordie Shore cast member and star of the first series, Vicky Pattison, would be making her return as an ex alongside Series 2 star Rogan O'Connor. The Only Way Is Essex cast member Kirk Norcross was also confirmed to be taking part in the series, with his ex-fiancée and Celebrity Big Brother star Cami-Li featuring as his ex. Star of Magaluf Weekender Jordan Davies was also revealed to be taking part in the series, also featuring as an ex. Megan McKenna and Jordan later returned for the fourth series. On 5 January 2016, cast member Megan McKenna entered the Celebrity Big Brother house to compete in the seveneeth series, and on 28 July 2016, Stephen Bear entered the house to compete in the eighteenth series where he left as the winner. Jordan Davies made another return to the show, this time during the fifth series with Jemma and Bear, and Holly also returning as an ex again. In August 2017, both Jemma Lucy and Jordan Davies took part in the twentieth series of Celebrity Big Brother.
 Links: a. Stephen Bear b. Stephen Bear c. The Only Way Is Essex d. Ibiza Weekender
Example Output: a

Example Input: Question: When did the war end that brought the inhabitants of New Mexico under the governance of the United States? Passage:Hispanos identify strongly with their Spanish heritage and most are also mestizos of mixed Apache, Comanche, Pueblo, Navajo, Native Mexican, and Genízaro ancestry. Exact numbers for the population size of New Mexican Hispanos is difficult, as many also identify with Chicano and Mexican-American movements. For most of its modern history, New Mexico existed on the periphery of the Spanish empire from 1598 until 1821 and later Mexico (1821–1848), but was dominated by Comancheria politically and economically from the 1750s to 1850s. Due to the Comanche, contact with the rest of Spanish America was limited, and New Mexican Spanish developed closer trading links with the Comanche than the rest of New Spain. In the meantime, some Spanish colonists coexisted with and intermarried with Puebloan peoples and Navajos, enemies of the Comanche. New Mexicans of all ethnicities were commonly enslaved by the Comanche and Apache of Apacheria, while Native New Mexicans were commonly enslaved and adopted Spanish language and culture. These Genízaros served as house servants, sheep herders, and in other capacities in New Mexico including what is known today as Southern Colorado well into the 1800s. By the late 18th century, Genízaros and their descendants, often referred to as Coyotes, comprised nearly one-third of the entire population of New Mexico. After the Mexican–American War, New Mexico and all its inhabitants came under the governance of the English-speaking United States, and for the next hundred years, English-speakers increased in number. By the 1980s, more and more Hispanos were using English instead of New Mexican Spanish at home.
 Links: a. Mexican–American War b. New Spain c. Apache d. Genízaro
Example Output:
a