This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Sleep Disorders, Subject name: Psychiatry
[{'content': 'Which about the following is false about narcolepsy? \nSelect and explain. \nA. Sleep sudden, B. Presents in 2nd decade, C. Cataplexy, D. Loss of muscle tone', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. Present in 2nd decadeNarcolepsy: Excessive daytime sleepiness, Cataplexy, Hypnagogic or hypnopompic hallucinations, sleep paralysis.Can occur at any age, although most commonly in adolescence or early adulthood, usually before 30 years', 'role': 'assistant'}]