Definition: In this task, you're given five sentences, numbered 1 through 5, and two options a and b for possible titles for the story. Your job is to choose the title that better fits the story. Indicate your choice by 'a' or 'b'.
Input: Sentence 1: I purchased peanut butter from the store. Sentence 2: I decided to have a quick snack. Sentence 3: I open the peanut butter jar and the seal was broken. Sentence 4: You can tell someone has been in it. Sentence 5: I return the peanut butter for a refund. Choices: a. Old peanut butter. b. Old cellphone.

a