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: set a contains all the even numbers between 2 and 50 inclusive. set b contains all the even numbers between 62 and 110 inclusive. what is the difference between the sum of elements of set b and the sum of the elements of set a ?
Options: a. 1500, b. 3100, c. 4400, d. 6200, e. 7400

Ex Output:
a


Ex Input:
Problem: the speed of the boat in still water in 12 kmph. it can travel downstream through 54 kms in 3 hrs. in what time would it cover the same distance upstream ?
Options: a. 8 hours, b. 6 hours, c. 4 hours, d. 5 hours, e. 9 hours

Ex Output:
e


Ex Input:
Problem: each of the cucumbers in 100 pounds of cucumbers is composed of 99 % water, by weight. after some of the water evaporates, the cucumbers are now 93 % water by weight. what is the new weight of the cucumbers, in pounds ?
Options: a. 2, b. 15, c. 92, d. 96, e. 98

Ex Output:

b