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: The robot swept the floor. Sentence 2: The man realized his ring was missing. Sentence 3: He looked inside the robot. Sentence 4: He found his ring. Sentence 5: He got his ring cleaned professionally. Choices: a. Too Short. b. Robot.

b