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: Kate wanted the best formula for her newborn baby. Sentence 2: She did some research online about different formulas. Sentence 3: She found one that was the best. Sentence 4: She placed an order for it online. Sentence 5: She received it a week later. Choices: a. Best Formula. b. Lost Money.

a