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: the dimensions of a room are 10 m x 7 m x 5 m. there are 2 doors and 3 windows in the room. the dimensions of the doors are 1 m x 3 m. one window is of size 2 m x 1.5 m and the other 2 windows are of size 1 m x 1.5 m. the cost of painting the walls at rs. 3 per sq m is
Options: a. 2488, b. 378, c. 739, d. 474, e. 291
Example Output: d

Example Input: Problem: the average age of 17 persons in a office is 15 years. out of these, the average age of 5 of them is 14 years and that of the other 9 persons is 16 years. the age of the 15 th person is ?
Options: a. 39, b. 41, c. 45, d. 42, e. 50
Example Output: b

Example Input: Problem: if p and q are prime numbers, how many divisors does the product p ^ 4 * q ^ 5 have ?
Options: a. 30, b. 40, c. 45, d. 50, e. 56
Example Output:
a