John has noticed that every night he awakens to go to the restroom at about 4:00 AM. This is an example of a(n) __________
A) altered state of consciousness.
B) caffeine addiction.
C) circadian rhythm.
D) sleep apnea.

Question

Quizplus · Accepted Answer

The fact that John wakes up every night at the same time to urinate indicates that his body is following a circadian rhythm. The circadian rhythm is the body's internal clock that regulates biological processes over a 24-hour period, including periods of sleep and wakefulness, as well as physiological functions like hunger and hormonal changes.

John Has Noticed That Every Night He Awakens to Go