This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
Waking up at night, screaming with fear, at 2.5 years age, is generally a manifestation of – 
Select and explain. 
A. Organic illness, B. Normal development pattern, C. Castration anxiety, D. Separation anxiety
D: Separation anxiety
Answer: D: Separation anxiety 
Explanation: Separation anxiety disorder is characterized by unrealistic and persistent worries of possible harm befalling the affected child or his or her primary caregivers, reluctance to go to school or sleep without being hear the parents persistent avoidance of being alone, nightmares involving themes of separation numerous somatic symptoms and complaints of subjective distress.