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 bag of potatoes weighs 60 lbs divided by half of its weight. how much does the bag of potatoes weight ?
Options: a. 20 lb, b. 11 lb, c. 10 lb, d. 15 lb, e. 5 lb

Ex Output:
b


Ex Input:
Problem: if ( 2 ^ 16 ) ( 25 ^ s ) = 5 ( 10 ^ m ) what is the value of m ?
Options: a. 7, b. 8, c. 15, d. 16, e. 23

Ex Output:
d


Ex Input:
Problem: what is the maximum number e of 27 cubic centimetre cubes that can fit in a rectangular box measuring 8 centimetre x 9 centimetre x 12 centimetre ?
Options: ['a. 36', 'b. 32', 'c. 24', 'd. 21', 'e. 15']

Ex Output:

c