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.

Example Input: Problem: a particular library has 75 books in a special collection, all of which were in the library at the beginning of the month. these book are occasionally loaned out through an inter - library program. if, by the end of the month, 80 percent of books that were loaned out are returned and there are 67 books in the special collection at that time, how many books of the special collection were loaned out during that month ?
Options: a. 20, b. 30, c. 35, d. 40, e. 55
Example Output: d

Example Input: Problem: in a certain deck of cards, each card has a positive integer written on it, in a multiplication game a child draws a card and multiplies the integer on the card with the next large integer. if the each possible product is between 10 and 400, then the least and greatest integer on the card would be
Options: a. 3 and 15, b. 3 and 20, c. 4 and 13, d. 4 and 14, e. 5 and 14
Example Output: b

Example Input: Problem: what is the sum of all possible solutions to | x - 2 | ^ 2 + | x - 2 | = 20 ?
Options: a. - 1, b. 6, c. 7, d. 8, e. 14
Example Output:
d