You are given a mathematical question described with an open-ended vocabulary. Questions in this task involve real-world situations, describing a mathematical problem. You are also given 4 or 5 answer options (associated with "A", "B", "C", "D", "E"). Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. LaTeX mathematical format (the standard way to express mathematical expressions in the typesetting software known as LaTeX) is used to express equations. Each question is solvable with high school math knowledge. Give only one answer for each question.

Q: A certain pump can drain a full 375-gallon tank in 15 minutes. At this rate, how many more minutes would it take to drain a full 600-gallon tank?
(A)9 (B)15 (C)18 (D)24 (E)25

A: A
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Q: After 21 students were added to a class, there were four times as many students as before. How many students were in the class before the addition?
(A)3 (B)7 (C)11 (D)14 (E)17

A: B
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Q: Eva and Magnus took a road trip and shared the driving. Eva drove four times as many miles as Magnus drove. What percent of the total miles of the trip did Eva drive?
(A)70\% (B)75\% (C)80\% (D)85\% (E)90\%

A:
C
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