Given the task definition and input, reply with output. 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: Francis got mad at his mom one day. Sentence 2: To get back at her he decided to hide her necklace. Sentence 3: He wanted to think of a great hiding place. Sentence 4: He decided to hide it behind the refrigerator. Sentence 5: His mom never found it. Choices: a. Invited. b. The Hidden Necklace.
b