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: 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.
Example output: c
Example explanation: The passage describes the 704th's actions during Operation Market Garden.
Q: Question: How old was Eric Temple Bell when Ross was an assistant professor at St. Louis University? Passage:Ross married Bertha (Bee) Halley Horecker, a singer-musician and daughter of Ross's Chicago neighbors, in 1931, received a National Research Council Fellowship for 1932, and worked as a National Research Council postdoctoral fellow at California Institute of Technology with Eric Temple Bell until 1933. Ross moved back to Chicago and led the mathematics department at an experimental school started by Ph.D.s during the Great Depression, People's Junior College, where he also taught physics. Ross became an assistant professor at St. Louis University in 1935 and stayed for about 11 years. In an interview, he said he advocated for a student who became the first black woman in the South to receive a master's degree in mathematics. This exception led the university to admit black students despite the idea's widespread unpopularity. During World War II, Ross served as a research mathematician for the U.S. Navy. He befriended Hungarian mathematician Gabor Szego while in St. Louis, who recommended Ross for a 1941 Brown University summer school that prepared young scientists to assist in the war, a program Ross attended. He occasionally worked on proximity fuzes for Stromberg-Carlson's laboratory from 1941 to 1945 before accepting a position as head of University of Notre Dame's mathematics department in 1946. He set out to change the school's research climate by inviting distinguished mathematicians including Paul Erdos, whom Ross made a full professor.
Links: a. Gabor Szego b. Saint Louis University c. Paul Erdos d. Eric Temple Bell
A:
d