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: Jill was very conscientious about her oral health. Sentence 2: She used the same type of toothbrush every day. Sentence 3: She noticed one day the blue in her toothbrush was fading. Sentence 4: Jill went to the store later to pick up a new one but they were out. Sentence 5: She wound up buying a new type of toothbrush and she liked it more. Choices: a. Toothpaste. b. unwanted diet.
a