Cindi prefers to take exams in the late afternoon rather than during the morning, because her energy level and ability to concentrate are better at that time.

Her experience most likely reflects the influence of the:

A. REM rebound.

B. menstrual cycle.

C. circadian rhythm.

D. hypnagogic state

C. circadian rhythm is the correct answer.

Explanation:

Cindi is suffering from Circadian rhythm sleep disorders in this case patients have excessive sleepiness during morning time that why she prefers to take exams in the late afternoon rather than during the morning because her energy level and ability to concentrate are better at that time.

Circadian rhythm is a natural process that controls the sleep and wake cycle and happens about every 24 hrs.

Circadian rhythm affects sleep, hormones, hunger, body temperature, and different body functions.

Abnormal circadian rhythms cause sleep disorders, diabetes, bipolar disorder, obesity, and depression.