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: An Old Friend. Sentence 1: After taking a long trip, Billy came back to town. Sentence 2: He walked down main street and into a coffee shop. Sentence 3: In the show he saw his friend, James. Sentence 4: James was very excited to see Billy for the first time in years. Choices: a. James bought Billy a cup of coffee to celebrate. b. I feel Harry is a disturbed child.
a