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: Troy's son was getting too big for his bike. Sentence 2: The boy's birthday was coming up soon. Sentence 3: Troy decided to buy him a bigger bike. Sentence 4: His son loved the new bike. Sentence 5: They donated the old bike to a center in town. Choices: a. A Bigger Bike. b. Epitome of laziness.

a