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: 10, 1000, 100000, 10000000....
Options: a. 100, 000,000, b. 1,000, 000,000, c. 1, 000,000, 000,000, d. 100, e. 1, 000,000
Example Output: b

Example Input: Problem: find the value o f 72519 x 9999 = m ?
Options: a. 434539873, b. 355797990, c. 435453490, d. m = 725117481, e. 873430134
Example Output: d

Example Input: Problem: a number when divided by 133 leaves 16 as a remainder. what will be the remainder if the number is divided by 50 ?
Options: a. 51, b. 56, c. 49, d. 17, e. 7
Example Output:
c