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: The man sprinted down the track. Sentence 2: His friend sprinted faster than him. Sentence 3: He practiced sprinting for three months. Sentence 4: He became faster than his friend. Sentence 5: He made fun of his friend for being too slow. Choices: a. Sprint. b. Fred chokes.

a