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: 3 candidates in an election and received 6136, 7636 and 11628 votes respectively. what % of the total votes did the winning candidate got in that election ?
Options: a. 46 %, b. 49 %, c. 57 %, d. 59 %, e. 61 %

Ex Output:
a

Ex Input:
Problem: trapezoid jklm in the x - y plane has coordinates j = ( 3, 4 ), k = ( 3, 1 ), l = ( 5, 7 ), and m = ( 5, 4 ). what is its perimeter ?
Options: a. 34, b. 36, c. 38, d. 40, e. ( f ) 42

Ex Output:
a

Ex Input:
Problem: an engineer designed a ball so that when it was dropped, it rose with each bounce exactly one - half as high as it had fallen. the engineer dropped the ball from a 16 - meter platform and caught it after it had traveled 45 meters. how many times did the ball bounce ?
Options: a. 5, b. 4, c. 7, d. 8, e. 9

Ex Output:
b