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: Kevin was walking down the street. Sentence 2: He saw a car run a stop sign. Sentence 3: The car hit a van. Sentence 4: Kevin ran over to the scene. Sentence 5: He helped the victims at the scene. Choices: a. Tattoo. b. Witness.

b