This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumors, Subject name: Ophthalmology
[{'content': 'Voex vein invasion is a feature of \nSelect and explain. \nA. Malignant melanoma, B. Retinoblastoma, C. Medulloepithelioma, D. Optic nerve glioma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Malignant melanoma of choroid shows extraocular spread along the perivascular spaces of the voex veins or ciliary vessels. Extraocular extension also occurs due to progressive growth of the tumor that may burst through sclera, usually at the limbus Ref. Khurana page no.174', 'role': 'assistant'}]