You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Ex Input:
Question: If x and y are negative integers, which of the following statements must be true?
I. (-x)^y is positive.
II. (-x)^(-y) is positive.
III. x^(-y) is positive.

Option A: None

Option B: II only

Option C: I and II

Option D: I and III

Option E: I, II and III

Ex Output:
Option C

Ex Input:
Question: If x is an integer such that 5 < x < 21, 7 < x < 18, 13 > x > 2, 12 > x > 9, and x + 1 < 13, then x is

Option A: 3

Option B: 5

Option C: 7

Option D: 9

Option E: 11

Ex Output:
Option E

Ex Input:
Question: The cost to rent a small bus for a trip is x dollars, which is to be shared equally among the people taking the trip. If 5 people take the trip rather than 15, how many more dollars, in terms of x, will it cost per person?

Option A: x/6

Option B: x/16

Option C: x/40

Option D: 3x/40

Option E: 3x/22

Ex Output:
Option E