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: Perry had a very comfortable hat. Sentence 2: After a long time, the hat became very messy. Sentence 3: He had to buy a new hat. Sentence 4: Perry spent a very long time finding the perfect hat. Sentence 5: Finally, Perry found the perfect hat. Choices: a. Books. b. Hat.

b