Given the task definition and input, reply with output. 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: Jack needed a new phone. Sentence 2: He finally found the one he wanted. Sentence 3: He ordered it online. Sentence 4: When the phone came in, it was broken. Sentence 5: Jack was extremely disappointed. Choices: a. New phone. b. Rental Car.
a