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: Casey was five and she really wanted a puppy. Sentence 2: Her parents told her they couldn't have a puppy right now. Sentence 3: Every day for a year, Casey asked about having a puppy. Sentence 4: Finally Christmas day came. Sentence 5: That morning, Casey cried when her gift was a new puppy! Choices: a. Exam Day. b. Christmas Puppy.
Output:
b