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: Biking. Sentence 1: Walker enjoyed biking every day. Sentence 2: He biked so much that his bike broke down. Sentence 3: He had to get a lot of expensive repairs done. Sentence 4: After the bike was repaired it was as good as new. Choices: a. Walker then biked with his friends as well. b. After many months, Joshua had a good arm.
b