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: Consider Input: Problem: a fort had provision of food for 150 men for 45 days. after 10 days, 25 men left the fort. find out the number of days for which the remaining food will last.
Options: a. 44, b. 42, c. 40, d. 38, e. 36

Output: b


Input: Consider Input: Problem: a sum of money at simple interest amounts to rs. 720 after 2 years and to rs. 1020 after a further period of 5 years. the sum is :
Options: a. 400, b. 500, c. 600, d. 700, e. 800

Output: c


Input: Consider Input: Problem: if a man walks at a rate of 10 kmph, he misses a train by 14 minutes. however, if he walks at the rate of 12 kmph, he reaches the station 10 minutes before the arrival of the train. find the distance covered by him to reach the station.
Options: a. 6, b. 15, c. 12, d. 4, e. 8


Output: a