Darla did not get any sleep during the previous night as she was studying for her mid-term exams. Tonight when she falls asleep she will likely experience __________

A) REM rebound.
B) NREM rebound.
C) sleep apnea.
D) night terrors.

REM rebound is the tendency to experience an increase in the length, depth, and frequency of REM sleep following a period of sleep deprivation. Since Darla did not get any sleep the previous night, it is likely that she will experience an increase in her REM sleep when she falls asleep, which is referred to as REM rebound. Option B, NREM rebound, is not applicable since NREM sleep does not show a rebound effect after sleep deprivation. Option C, sleep apnea, refers to a sleep disorder characterized by interrupted breathing during sleep and option D, night terrors, refers to a type of sleep disorder that is characterized by feelings of terror or dread during sleep, accompanied by physical symptoms such as sweating, rapid heart rate, and confusion. These options are not relevant to the scenario described in the question.