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
Dreaming is charactersitic of- 
Select and explain. 
A. REM sleep, B. Stage II NREM sleep, C. Stage IV NREM sleep, D. Stage I NREM sleep
A: REM sleep
Answer: A: REM sleep 
Explanation: 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.