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 perimeter of a square field whose diagonal is 8 â ˆ š 2 ?
Options: a. 64 m, b. 32 m, c. 30 m, d. 16 m, e. 18 m

Ex Output:
b


Ex Input:
Problem: a can do a piece of work in 4 hours; b and c together can do it in 3 hours, while a and c together can do it 2 hours. how long will b alone take to do it ?
Options: a. 8 hours, b. 10 hours, c. 12 hours, d. 24 hours, e. none of these

Ex Output:
c


Ex Input:
Problem: if 2 ^ 5, 3 ^ 3, and 14 ^ 2 are all factors of the product of 936 and w where w is a positive integer, what is the smallest possible value of w ?
Options: a. 26, b. 39, c. 42, d. 65, e. 168

Ex Output:

e