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: Fans of Clark. Sentence 1: A heat wave swept the city one summer. Sentence 2: Clark was concerned about his elderly neighbors. Sentence 3: They did not have air conditioning. Sentence 4: Clark bought several large fans for his neighbors. Choices: a. They were thankful to have some relief from the heat. b. She knit blue into the yarn blanket.
b