In this task, you're given the title of a five-sentence story, the first four sentences, and two options for the fifth sentence as a and b. Your job is to pick the sentence option that seamlessly connects with the rest of the story, indicating your choice as 'a' or 'b'. If both sentences are plausible, pick the one that makes more sense.

Title: Forger Caught. Sentence 1: A prescription forger visited my store's pharmacy. Sentence 2: He dropped off a fake prescription to be filled. Sentence 3: The pharmacy manager notified the police. Sentence 4: The police were waiting when he returned for his medicine. Choices: a. Luckily his protest worked and they managed to avoid that tree. b. They arrested him when he walked out of the door.
b