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: the total age of a and b is 12 year more than the total age of b and c. c is how many years younger than a ?
Options: a. 12, b. 24, c. data inadequate, d. none of these, e. 34

Ex Output:
a


Ex Input:
Problem: a sum of money at simple interest amounts to rs. 720 after 2 years and to rs. 1020 after a further period of 5 years. the sum is :
Options: a. 400, b. 500, c. 600, d. 700, e. 800

Ex Output:
c


Ex Input:
Problem: the sum of 3 integers is 33. the largest integer is 3 times the middle integer, and the smallest integer is 23 less than the largest integer. what is the product of the 3 integers ?
Options: a. 192, b. 203, c. 214, d. 225, e. 236

Ex Output:

a