There is one choice missing from this question:
a. narcoleptic fits
b. nightmares
c. apnea episodes
d. night terrors*
The correct answer is "night terrors". Night terrors are intense feelings at the first half of non-REM sleep that is characterized by fear, horror, trembling, shaking. Night terrors are different from nightmares as there are physical effects carried out from night terrors upon waking up such as screaming, crying, and sudden movements.