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: what is the rate percent when the simple interest on rs. 810 amount to rs. 155 in 4 years ?
Options: a. 4.78, b. 4.68, c. 4.58, d. 4.48, e. 4.38

Output: a


Input: Consider Input: Problem: the average of first five multiples of 7 is :
Options: a. 9, b. 16, c. 15, d. 8, e. 21

Output: e


Input: Consider Input: Problem: the malibu country club needs to drain its pool for refinishing. the hose they use to drain it can remove 60 cubic feet of water per minute. if the pool is 60 feet wide by 100 feet long by 10 feet deep and is currently at 80 % capacity, how long will it take to drain the pool ?
Options: a. 1000, b. 1400, c. 1200, d. 800, e. 1000


Output: d