The period of sleep during which the brain is very active, voluntary muscle activity becomes suppressed, there is considerable physiological arousal, and one's eyes move back and forth under closed eyelids is called:

REM Sleep

Explanation:

Rapid eye movement (REM) sleep may be defined as the sleep that involves the rapid and random movement of the eyes. The muscle tone gets low during the REM sleep.

The brain is quite active and desynchronized brain waves are recorded in the REM sleep. The individual brain is quite active as the awake person's mind during REM sleep.

Thus, the correct answer is REM sleep.

exercising at a moderate intensity, and slowly increasing the duration.

the andrews is b

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