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: michelle deposited a certain sum of money in a savings account on july 1 st, 2007. she earns an 14 % interest compounded semiannually. the sum of money in the account on december 31 st, 2009 is approximately what percent of the initial deposit ?
Options: a. 117 %, b. 120 %, c. 121 %, d. 138 %, e. 145 %

Ex Output:
d


Ex Input:
Problem: john and david can finish a job together in 2 hours. if john can do the job by himself in 3 hours, what percent of the job does david do ?
Options: a. 36.33 %, b. 33.33 %, c. 39.33 %, d. 40.33 %, e. 33 %

Ex Output:
b


Ex Input:
Problem: positive integer y is 50 percent of 50 percent of positive integer x, and y percent of x equals 100. what is the value of y ?
Options: a. 50, b. 100, c. 200, d. 1,000, e. 2,000

Ex Output:

a