Given the task definition and input, reply with output. You are given a sentence, a question and two answer options ('A' and 'B'). Your task is to find the correct answer (return the string of the correct option, not 'A' or 'B') for the given question.

Sentence: Mike's tortilla chips get hotter rattling around in his bag compared to when they rattle around inside of a box. Question: Which item has the smoothest sides? (A) bag (B) box
box