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 primary tumor of orbital cavity presenting as proptosis is 
Select and explain. 
A. Cavernous hemangioma, B. Retinoblastoma, C. Malignant melanoma, D. Uveal melanoma
A: Cavernous hemangioma
Answer: A: Cavernous hemangioma 
Explanation: None