Instructions: 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.
Input: Problem: a pump can fill a tank with a water in 2 hours. because of a leak, it took 3 and 1 / 3 hours to fill the tank. the leak can drain all the water of the full tank in how many hours ?
Options: a. 5 hrs, b. 7 hrs, c. 12 hrs, d. 14 hrs, e. 16 hrs
Output:
a