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: walking at 4 / 5 of her normal speed, a worker is 10 minutes later than usual in reaching her office. the usual time ( in minutes ) taken by her to cover the distance between her home and her office is
Options: a. 30, b. 35, c. 40, d. 45, e. 50

Ex Output:
c


Ex Input:
Problem: out of 3 consecutive odd numbers 11 times the first number is equal to addition of thrice the third number and adding 16 to 4 times the second. what is the first number ?
Options: a. 5, b. 6, c. 7, d. 8, e. 9

Ex Output:
e


Ex Input:
Problem: in a garden, there are 10 rows and 12 columns of mango trees. the distance between the two trees is 2 m and a distance of one meter is left from all sides of the boundary of the length of the garden is :
Options: a. 450 sq mtrs, b. 460 sq mtrs, c. 480 sq mtrs, d. 490 sq mtrs, e. 470 sq mtrs

Ex Output:

c