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: Geography. Sentence 1: Beth was teaching Geography to a class of 7th Grade students. Sentence 2: All of the students were having fun, because they liked her teaching. Sentence 3: One day, Beth didn't come to school because she was sick. Sentence 4: A substitute teacher came to teach her class for her. Choices: a. After hours of sightseeing I was done and had a great experience. b. All of the students were sad that she was gone.
a