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
[{'content': 'Most common orbital tumor in children: \nSelect and explain. \nA. Rhabdomyosarcoma, B. Retinoblastoma, C. Melanoma, D. Chloroma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e.Rhabdomyosarcoma', 'role': 'assistant'}]