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.

[Q]: Title: Can't Do Simple Math. Sentence 1: At the cash register a customer held out a credit card to Jenny. Sentence 2: Next the customer said, wait, I have a twenty, a passed the bill. Sentence 3: But, now, Jenny's register won't calculate the change. Sentence 4: There wasn't a pen or paper nearby so Jenny could do the math. Choices: a. Luckily her family ate them anyway. b. She couldn't in her head and the customer said, can't do simple math?
[A]: a

[Q]: Title: Dance Class. Sentence 1: Natalie was going to her first dance class. Sentence 2: She had dreamed about this day for years! Sentence 3: Her teacher invited her to put on her ballet shoes. Sentence 4: Natalie couldn't wait to learn how to dance! Choices: a. She was going to work hard to do a great job in the recital. b. But her boss congratulated her as she had found the quips funny.
[A]: b

[Q]: Title: rust. Sentence 1: The metal rusted. Sentence 2: Nobody did anything about it. Sentence 3: One day the part broke. Sentence 4: It hurt somebody. Choices: a. The insurance company blamed it on negligence. b. Karina ate a waffle after she ate her apple.
[A]:
b