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': 'Malignant melanoma of the choroid of following histological features has got the best prognosis: \nSelect and explain. \nA. Epitheloid cell melanoma, B. Spindie - A melanoma, C. Spindle - B melanoma, D. Mixed cell melanoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. Spindie - A melanoma', 'role': 'assistant'}]