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: Billy did not like the basement. Sentence 2: It was dark and cold. Sentence 3: His ball had fallen down the stairs. Sentence 4: He did not go down in the basement. Sentence 5: He made his dad get the ball. Choices: a. Reunion. b. The Basement.

b