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: Have any of the original members of Rage Against the Machine ever divorced? Passage:Audioslave's history dates back to October 18, 2000, when Rage Against the Machine's lead vocalist Zack de la Rocha announced he was leaving the band, citing a breakdown in its "decision-making process". This led to the breakup of Rage Against the Machine, but the remaining three members of the bandTim Commerford, Tom Morello, and Brad Wilkdecided to stay together and announced plans to continue with a new vocalist. Several vocalists jammed with the three, including B-Real of Cypress Hill, but they did not want another rapper or anybody who sounded like de la Rocha. Contrary to popular belief, Layne Staley of Alice in Chains neither auditioned nor was asked to join the new project. Tom Morello denied this claim on his Twitter account in 2015. Music producer and friend Rick Rubin suggested that they play with Chris Cornell of Soundgarden. Rubin also persuaded the three of them to go into group therapy with performance coach Phil Towle after the breakup. Rubin was confident that with the right new voice, Rage Against the Machine had the potential to become a better band; he believed "it could turn into a Yardbirds-into-Led Zeppelin scenario." Commerford later credited Rubin for being the catalyst that brought Audioslave together. He called him "the angel at the crossroads" because "if it wasn't for him, I wouldn't be here today."
Links: a. Rage Against the Machine b. Layne Staley c. Zack de la Rocha d. Tim Commerford

Ex Output:
d

Ex Input:
Question: How long did the war that Potter fought in as an officer in the Royal Field Artillery last? Passage:Potter was born in Bedford to Reverend Brignal Peel, a Wesleyan minister, and Elizabeth Stimson. He was educated at Bedford Modern School and for a time at Worcester College, Oxford. He first performed in E. M. Royle's The White Man at the Lyric Theatre in London before touring. In 1915 he was George Robey's understudy at the Alhambra. During the Great War Potter served as a 2nd lieutenant in the Royal Field Artillery in France. He served in the 6th Division 2nd Brigade 21st Battery, from 8 February 1917 before returning to music hall once the war was over. Potter cultivated an individual style and persona, wearing a straw boater, wide grey flannel trousers (he said he invented the Oxford bags style at the Coliseum in 1920), an 'Old Borstolian' blazer and carrying a notebook with a rolled umbrella. James Agate described him as "that sham Harrovian who bears upon his blazer the broad arrows of a blameful life".
Links: a. Harrow School b. World War I c. Lyric Theatre, London d. World War I

Ex Output:
b

Ex Input:
Question: How long is the river that bordered the land occupied by Bavarians? Passage:In the meantime, the Germanic tribe of the Bavarii (Bavarians), vassals of the Franks, had developed in the 5th and 6th century in the west of the country and in what is now known as Bavaria, while what is today Vorarlberg had been settled by the Alemans. In the northern alps the Bavarians had become established as a stem dukedom around 550 AD, under the rule of the Agilolfings until 788 as an eastern outpost of the Frankish Empire. At that time the lands occupied by the Bavarians extended south to current South Tyrol, and east to the river Enns. The administrative center was at Regensburg. Those groups mixed with the Rhaeto-Romanic population and pushed it up into the mountains along the Puster Valley.
Links: a. Enns (river) b. Francia c. Enns (river) d. South Tyrol

Ex Output:
a