Instructions: 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.
Input: Title: Birthday fun. Sentence 1: Allie had a birthday. Sentence 2: She took them to the casino. Sentence 3: When they got there they had some fun. Sentence 4: Her friend won something. Choices: a. It was a productive day. b. He said he would fix my tooth.
Output:
a