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: It began storming again when we least expected it. Sentence 2: It started early in the morning, and continued past noon. Sentence 3: It dumped so much water that we received a flood warning. Sentence 4: We began to worry as the yard got deep with water. Sentence 5: Finally it stopped, and we breathed a sigh of relief. Choices: a. Thunder. b. Going Home.
a