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: Bill and Mary were a married couple. Sentence 2: They really wanted kids but were unable to conceive. Sentence 3: This pained Bill and Mary quite a lot. Sentence 4: One day Bill came home and Mary was smiling and beaming. Sentence 5: She told Bill that she was finally and undeniably pregnant! Choices: a. Paper. b. Baby!.

b