Given the task definition and input, reply with output. 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: Jackie had a message from her sister when she got home from worker. Sentence 2: The message told her to meet Gina at the gym at 7pm. Sentence 3: When she got there, she saw Gina waiting outside a classroom. Sentence 4: Gina had signed them both up for a self-defense class. Sentence 5: She never had so much fun in her life. Choices: a. Self-Defense Class. b. Church.
a