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.

Example 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']
Example Output: a

Example Input: Problem: a batsman makes a score of 87 runs in the 17 th inning and thus increases his average by 3. find his average after 17 th inning.
Options: a. 39, b. 88, c. 26, d. 87, e. 11
Example Output: a

Example Input: Problem: if p and q are both odd prime numbers andp < q, then how many different positive integer factors does 2 pqhave ?
Options: a. 3, b. 4, c. 6, d. 8, e. 12
Example Output:
d