Night Terrors Are Different from Nightmares in That ____

 Night terrors are different from nightmares in that ____. 

A) nightmares occur more often in children and night terrors occur more often in adults
B) nightmares typically occur during REM sleep and night terrors typically occur during deep sleep
C) nightmares are not easily recalled in the morning but night terrors are often vividly recalled
D) the causes of nightmares are not easily understood, while night terrors are clearly a result of stress