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 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: The Blue ball. Sentence 1: It was time to play games with my friends. Sentence 2: We had four balls to play with. Sentence 3: The best was the blue ball. Sentence 4: Unfortunately, my friend Tim wanted to play with it. Choices: a. He had been using my conditioner and thought it was shampoo. b. We both decided to compromise and share the blue ball.
b