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: if a lends rs. 3150 to b at 8 % per annum and b lends the same sum to c at 12.5 % per annum then the gain of b in a period of 2 years is ?
Options: a. 280, b. 295, c. 283.5, d. 245, e. 200

Ex Output:
c


Ex Input:
Problem: students at a school were on average 180 cm tall. the average female height was 170 cm, and the average male height was 182 cms. what was the ratio of men to women ?
Options: a. 5: 2, b. 5: 1, c. 4: 3, d. 4: 1, e. 3: 1

Ex Output:
b


Ex Input:
Problem: at what rate percent on simple interest will rs. 1500 amount to rs. 2000 in 5 years ?
Options: a. 8.33 %, b. 3 6 / 7 %, c. 2 6 / 7 %, d. 5 %, e. 6 %

Ex Output:

a