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: Lisa was having a sleepover with several friends. Sentence 2: But there weren't enough beds for everyone. Sentence 3: Three of Lisa's friends decided to share a bed. Sentence 4: But when they got on, the legs of the bed frame broke. Sentence 5: Everyone agreed to help Lisa pay for a new bed frame. Choices: a. Sienna's Birthday. b. Broken Bed.

b