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: the l. c. m of two numbers is 495 and their h. c. f is 5. if the sum of the numbers is 100, then their difference is
Options: a. 19, b. 10, c. 28, d. 27, e. 29

Ex Output:
b


Ex Input:
Problem: ages of two persons differ by 20 years. if 6 year ago, the elder one be 3 times as old the younger one, find their present age
Options: a. 12,28, b. 14,30, c. 16,36, d. 18,34, e. 19,34

Ex Output:
c


Ex Input:
Problem: a certain sum of money is divided among a, b and c so that for each rs. a has, b has 65 paisa and c 40 paisa. if c ' s share is rs. 56, find the sum of money ?
Options: a. 288, b. 287, c. 72, d. 205, e. 267

Ex Output:

b