Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Ex Input:
Problem: what is the smallest positive integer x such that 66 - x is the cube of a positive integer
Options: a. 5, b. 7, c. 47, d. 9, e. 2

Ex Output:
e


Ex Input:
Problem: find the maximum value of the function f ( x ) = x − 5 if x is a number between - 5 and 13.
Options: a. 6, b. 7, c. 8, d. 9, e. none

Ex Output:
c


Ex Input:
Problem: a number when divided by a divisor leaves a remainder of 23. when twice the original number is divided by the same divisor, the remainder is 11. what is the value of the divisor ?
Options: a. 12, b. 13, c. 35, d. 36, e. 59

Ex Output:

d