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.

Ex Input:
Problem: if a person walks at 25 km / hr instead of 10 km / hr, he would have walked 20 km more. the actual distance traveled by him is :
Options: a. 50 km, b. 56 km, c. 13.3 km, d. 70 km, e. 80 km

Ex Output:
c


Ex Input:
Problem: when 242 is divided by a certain divisor the remainder obtained is 15. when 698 is divided by the same divisor the remainder obtained is 27. however, when the sum of the two numbers 242 and 698 is divided by the divisor, the remainder obtained is 5. what is the value of the divisor ?
Options: a. 11, b. 17, c. 13, d. 23, e. 37

Ex Output:
e


Ex Input:
Problem: the price of precious stone is directly proportional to square of its weight. what will be the loss incurred if a stone weighing 28 gm and costing 28,000 breaks into two pieces whose weights are in the ratio 15: 13 ?
Options: a. no loss, b. 10,000, c. 28,000, d. 9,500, e. 14,000

Ex Output:

e