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: Sarah was excited about going on the trip. Sentence 2: Her and her friends were going to float down the river. Sentence 3: They had all bought tubes to float down the river in. Sentence 4: The day came and they all jumped on their tubes in the river. Sentence 5: They spent the day floating, relaxing, and having a good time. Choices: a. An Old Friend. b. Going Down the River.

b