This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Sleep Physiology, Subject name: Physiology
[{'content': 'Dreaming is charactersitic of- \nSelect and explain. \nA. REM sleep, B. Stage II NREM sleep, C. Stage IV NREM sleep, D. Stage I NREM sleep', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., REM sleep o Features of REM sleep are: -i) EEG - Beta-wave, Reappearance of alpha wave, Saw-tooth wave (low voltage fast activity), Ponto-genital- occipital spikes.ii) Dreamingiii) Other features :- Generalized muscular atony, Penile erection, autonomic hyperactivity (Increased pulse rate & BP) and intermittent movement of small muscle groups.", 'role': 'assistant'}]