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: Ramon was used to finding rats in his basement. Sentence 2: But when he found a whole family that took the cake. Sentence 3: It didn't feel right to kill a whole family. Sentence 4: So instead of calling the exterminator, he built them a small house. Sentence 5: A month later they had doubled in size and took over. Choices: a. Rats. b. The Bridge.
Output:
a