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: a and b together can complete work in 6 days. a alone starts working and leaves it after working for 4 days completing only half of the work. in how many days it can be completed if the remaining job is undertaken by b ?
Options: a. 4, b. 12, c. 5, d. 6, e. 7

Output: b


Input: Consider Input: Problem: a library branch originally contained 18360 volumes, 30 % of which were fiction novels. 1 / 3 of the volumes were transferred to another location and 1 / 5 of the volumes transferred were fiction novels. what percent of the remaining collection was fiction novels ?
Options: a. 2.5 %, b. 17.67 %, c. 28.3 %, d. 36 %, e. 73.6 %

Output: d


Input: Consider Input: Problem: the number obtained by interchanging the digits of a two - digit number is less than the original number by 36. the sum of the digits of the number is 8. what is the original number ?
Options: a. 71, b. 62, c. 53, d. 35, e. 45


Output: b