From the story flowers for algernon

Which of these situations would most likely arouse suspicion?

A. You are running late for school, and your little sister is ready to go.
B. You are studying for a test, and your little sister is working on her homework.
C. Your piece of cake is missing, and your little sister has chocolate stains on her shirt.
D. Your piano recital is on Saturday, and your little sister has invited two of her friends to attend.