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: Mark goes to the dentist. Sentence 1: Mark went to the dentist for the first time in two years. Sentence 2: He had a cleaning, exam and x-rays done by the dentist. Sentence 3: After the exam, the dentist told Mark he had three cavities. Sentence 4: Mark was relieved that was all he had. Choices: a. He made an appointment for the fillings and went home happy. b. Clark goes to the doctor and they tell him he has scabies.
b

Title: Wrong Alert. Sentence 1: Sarah walked into library. Sentence 2: The metal detector made a sound as soon as she walked through it. Sentence 3: A security guard pulled her to the side of the detector. Sentence 4: He ran a quick search. Choices: a. He didn't notice anything except her earrings. b. The ceiling did not leak the next time it rained.
b

Title: Nightmare. Sentence 1: Stephanie awoke in the middle of the night to a door slamming. Sentence 2: She became very scared, thinking she had an intruder in her home. Sentence 3: Stephanie grabbed her pepper spray and tiptoed downstairs. Sentence 4: She noticed her back door was ajar and quietly walked over to it. Choices: a. Tim saw his happiness improve significantly. b. She peered outside and saw her sleepwalking daughter roaming the yard.
a