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: a shopkeeper buys mangoes at the rate of 5 a rupee and sells them at 2 a rupee. find his net profit or loss percent ?
Options: a. 34 %, b. 30 %, c. 50 %, d. 150 %, e. 33 %

Ex Output:
d


Ex Input:
Problem: find the smallest number that should be multiplied with 54000 to make it a perfect cube.
Options: ['a. 4', 'b. 5', 'c. 6', 'd. 3', 'e. 7']

Ex Output:
a


Ex Input:
Problem: in a dance competition the points in each round for the first, second, third and fourth position were 10050, 2010. no other points were given. ashita participated in several rounds in the competition and the product of her score was 50000. in how many rounds did she participate ?
Options: a. 3, b. 2, c. 1, d. 5, e. can not be determined

Ex Output:

e