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: Exchange student. Sentence 1: Michelle was really excited to meet the new exchange student. Sentence 2: When she entered her class, she looked around impatiently. Sentence 3: There he was surrounded by everyone. Sentence 4: As she tried to make her way to talk to him too, she fell. Choices: a. So Alicia was very happy she got the job. b. The exchange student left the group in a hurry to help her back up.
b