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: if a sum of money doubles itself in 20 years at simple interest, the ratepercent per annum is
Options: a. 12, b. 12.5, c. 13, d. 5, e. 14

Output: d


Input: Consider Input: Problem: the average weight of a, b and c is 43 kg. if the average weight of a and b be 48 kg and that of b and c be 42 kg, then the weight of b is :
Options: a. 55 kg, b. 53 kg, c. 49 kg, d. 52 kg, e. 51 kg

Output: e


Input: Consider Input: Problem: to fill a tank, 25 buckets of water is required. how many buckets of water will be required to fill the same tank if the capacity of bucket is reduced to two - fifth of its present ?
Options: a. 52.5, b. 62.5, c. 72.5, d. 82.5, e. 81.5


Output: b