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: exactly 35 % of the reporters for a certain wire service cover local politics in country x. if 30 % of the reporters who cover politics for the wire service do not cover local politics in country x, what percent of the reporters for the wire service do not cover politics ?
Options: a. 20 %, b. 42 %, c. 44 %, d. 50 %, e. 84 %
Example Output: d

Example Input: Problem: a can give b 50 meters start and c 100 meters start in a kilometer race. how much start can b give c in a kilometer race ?
Options: a. 111.12, b. 111.67, c. 111.64, d. 52.63, e. 101.12
Example Output: d

Example Input: Problem: zachary is helping his younger brother, sterling, learn his multiplication tables. for every question that sterling answers correctly, zachary gives him 3 pieces of candy. for every question that sterling answers incorrectly, zachary takes away two pieces of candy. after 6 questions, if sterling had answered 2 more questions correctly, he would have earned 31 pieces of candy. how many of the 6 questions did zachary answer correctly ?
Options: a. 6, b. 7, c. 8, d. 9, e. 10
Example Output:
b