This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diseases of orbit, Lids and lacrimal apparatus, Subject name: Ophthalmology
[{'content': 'Which of the following tumours present with proptosis- \nSelect and explain. \nA. Neuroblastoma, B. Nephroblastoma, C. Germ cell tumour, D. Medulloblastoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Most common cause of bilateral proptosis: In children : Neuroblastoma and leukemia (chloroma). In adults : Thyroid ophthalmopathy. Most common cause of unilateral proptosis: In children : Orbital cellulitis. In adults : Thyroid ophthalmopathy. Other tumors causing proptosis : symmetrical lymphoma, secondaries from Neuroblastoma, nephroblastoma, Ewings, leukemic infiltration. Ref: A. K. Khurana 6thE pg404 ref img', 'role': 'assistant'}]