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: Shery was invited to her cousin's wedding. Sentence 2: She rearranged her work schedule so she could attend the wedding. Sentence 3: She ran into her cousin at the mall the day before the wedding. Sentence 4: Her cousin was upset that Shery hadn't come to the wedding. Sentence 5: Shery had written down the wrong date, she felt awful. Choices: a. Book. b. Big Mistake.

b