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.
Input: Problem: let s be the set of all positive integers that, when divided by 8, have a remainder of 5. what is the 70 th number in this set ?
Options: a. 557, b. 608, c. 613, d. 616, e. 621
Output:
a