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: Ophthalmology
Most common cause of unilateral proptosis in children is 
Select and explain. 
A. Thyroid ophthalmopathy, B. Orbital cellulitis, C. Chloroma, D. Neuroblastoma
B: Orbital cellulitis
Answer: B: Orbital cellulitis 
Explanation: M/C cause in children - Orbital cellulitis.
M/C cause in adults - Thyroid ophthalmopathy.