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 man lost 10 % by selling oranges at the rate of 12 a rupee at how many a rupee must he sell them to gain 44 % ?
Options: a. 6.5, b. 7.5, c. 7, d. 8, e. 2

Ex Output:
b


Ex Input:
Problem: sakshi can do a piece of work in 5 days. tanya is 25 % more efficient than sakshi. the number of days taken by tanya to do the same piece of work :
Options: a. 4, b. 16, c. 18, d. 25, e. 10

Ex Output:
a


Ex Input:
Problem: two boys starts from the same place walking at the rate of 5.5 kmph and 7.5 kmph respectively in the same direction. what time will they take to be 20 km apart ?
Options: a. 10, b. 11, c. 14, d. 15, e. 20

Ex Output:

a