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: Tom was set to run a marathon. Sentence 2: He was a favorite to win it. Sentence 3: At the beginning Tom tripped and hurt himself. Sentence 4: He wasn't able to keep running. Sentence 5: Tom had to forfeit. Choices: a. Falling Down. b. Shattered Window.

a