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'.

Sentence 1: Sara needed help with her tennis serve. Sentence 2: She hired a tennis pro to help her. Sentence 3: The pro helped improve her serve. Sentence 4: Sara's serve got much better. Sentence 5: She was able to win matches with just her serve. Choices: a. Tennis lessons. b. Glasshole.
a