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: Medicine
[{'content': "Multifocal tumour of vascular origin in a patient of AIDS is - \nSelect and explain. \nA. Kaposi's sarcoma, B. Astrocytoma, C. Gastric carcinoma, D. Primary CNS lymphoma", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]