Arousal is most difficult in which stage of sleep -
Ans is 'c' i.e., Stage 3,4 NREM'In general, the ease of arousal from sleep parallels the ordering of the sleep stages, with NEM and stage 1 being the easiest for arousal and stage 4 the most difficult.
Stage 1 NREM
Stage 2 NREM
Stage 3,4 NREM
REM