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: I noticed that my car was running hot. Sentence 2: I kept driving home. Sentence 3: I could not start it again. Sentence 4: I had cracked a head gasket. Sentence 5: I learned to stop when running hot. Choices: a. Overheating. b. Procrastination.

a