You will be given a definition of a task first, then some input of the task.
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: Abby was painting the center line on the highway. Sentence 2: He started daydreaming. Sentence 3: He looked back to see that the line was crooked. Sentence 4: He went back and painted over the line with black. Sentence 5: He got home three hours late from that mistake. Choices: a. Going Down the River. b. Painting Lines.
Output:
b