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: calculate the share of z, if rs. 3720 is divided among x, y and z in the ratio 7: 8: 11 ?
Options: a. 1564.1, b. 1214.1, c. 1574.1, d. 1271.1, e. 1044.1

Ex Output:
c


Ex Input:
Problem: a train 150 m long is running at a speed of 68 kmph. how long does it take to pass a man who is running at 8 kmph in the same direction as the train ?
Options: a. 2 sec, b. 6 sec, c. 8 sec, d. 9 sec, e. 5 sec

Ex Output:
d


Ex Input:
Problem: a can do a piece of work in 15 days. a does the work for 5 days only and leaves the job. b does the remaining work in 6 days. in how many days b alone can do the work ?
Options: a. 5 days, b. 7 days, c. 12 days, d. 9 days, e. 10 days

Ex Output:

d