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: Tom always paid his bills on time. Sentence 2: One day he got a letter saying he was late on a payment. Sentence 3: Tom didn't know why. Sentence 4: He called in to fix the problem. Sentence 5: He was told it was a mistake and things were fixed. Choices: a. late bills. b. Smart Phone.

a