Detailed Instructions: 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.
Problem:Problem: the sum of the even numbers between 1 and n is 85 * 86, where n is an odd number, then n = ?
Options: a. 163, b. 171, c. 179, d. 185, e. 191
Solution:
b