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: if price of t. v set is reduced by 20 %, then its sale increases by 80 %, find net effect on sale value
Options: a. 44, b. 45, c. 46, d. 47, e. 48
Example Output: a

Example Input: Problem: one side of a rectangular field is 14 m and one of its diagonal is 17 m. find the area of the field.
Options: a. 134.4, b. 120, c. 150, d. 180, e. none
Example Output: a

Example Input: Problem: in a group of 7 boys and 8 girls, 5 members are to be selected. in how many different ways can they be selected such that at least 3 boys should be there ?
Options: a. 1200, b. 1500, c. 1281, d. 1339, e. 1296
Example Output:
c