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'.
Q: Sentence 1: Alex really believed whatever anyone told him. Sentence 2: From lies to pranks, he fell for them all. Sentence 3: He decided that enough was enough. Sentence 4: In one case, someone asked him to open the door when the knob was hot. Sentence 5: He said no and gleefully walked away proud of himself. Choices: a. Rude friend. b. Ignorance.
A:
b