Given the task definition and input, reply with output. 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 does not connect with the rest of the story, indicating your choice as 'a' or 'b'. If both sentences are plausible, pick the one that makes less sense.

Title: Autistic Grandson. Sentence 1: My old boss has an autistic grandson. Sentence 2: Paul is five and cannot talk. Sentence 3: He was getting treatment but lately has been acting out. Sentence 4: Recently the family brought in a dog as a service animal. Choices: a. So far Paul has been calmer. b. Tom was never able to find it.
b