Given the task definition, example input & output, solve the new input case.
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: Question: When did the operation during which the 704th dropped supplies to allied troops near Nijmegen begin? Passage: The group was occasionally diverted from strategic missions to carry out air support and interdiction missions. It supported Operation Overlord, the invasion of Normandy by attacking transportation targets, including bridges, along with airfields and strong points in France. On D Day, the squadron and the rest of the 446th Group led the first heavy bomber mission of the day. The 446th aided ground forces at Caen and Saint-Loduring July by hitting bridges, gun batteries, and enemy troops. During Operation Market Garden, the attempt to seize a bridgehead across the Rhine in the Netherlands, the 704th dropped supplies to allied troops near Nijmegen. It struck lines of communications during the Battle of the Bulge. During Operation Varsity in March 1945, it supplied ground and airborne troops near Wesel. The squadron flew its last combat mission on 25 April 1945 against Salzburg, Austria. The group had flown 273 missions and had lost 58 aircraft during the war,
. Links: a. Allies of World War II b. Wesel c. Operation Market Garden d. Air Support.
Output: c
The passage describes the 704th's actions during Operation Market Garden.

New input case for you: Question: Was digoxin approved by the FDA? Passage:He was principal investigator on the REFLECT trial for flosequinan which ran from 1987-1989 and the following PROFILE trial from 1991-1994. He was PI on a study of amlodipine that ran from 1987-1989 and the following PRAISE trial from 1992-1995 and PRAISE 2 from 1996-1999; the PROMISE trial for milrinone 1988-1990; the ATLAS trial for lisinopril from 1993-1997; the PRECISE trial for carvedilol from 1993-1995 and the following COPERNICUS trial from 1997-2002; the ENABLE trial (1999-2001) and REACH-1 trial (1997-2003) for bosentan; the OVERTURE trial (1999-2002) for omapatrilat; REVIVE I and II (2001-2006) for levosimendan; and the TRUE-AHF trial of ularitide that started in 2013. He also chaired the steering committee for the RADIANCE trial from 1989-1992 which studied the use of digoxin in people who were also treated with ACE inhibitors and chaired the steering committee for the RENEWAL trial (1999-2002) for etanercept. He was also the co-PI of the PARADIGM-HF trial that led to the approval of valsartan/sacubitril.
Links: a. Omapatrilat b. Digoxin c. Digoxin d. Digoxin
Output:
b