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': "All are HIV associated malignancies except- \nSelect and explain. \nA. Kaposi's sarcoma, B. Lung carcinoma, C. NHL, D. Anogenital CA", 'role': 'user'}, {'content': 'Answer: B \nExplanation: AIDS-related lymphomas can be divided into three group -\nSystemic\n\n\nLymphomas involving lymph nodes as well as extranodal visceral sites constitute 80% of all lymphomas.\n\n\nThe most common extranodal site affected is CNS\n\n\nAggressive B cell tumours\n\n\nPrimary CNS\xa0lymphoma\n\n\nCNS is the primary site of lymphomatous involvement in 20% AIDS patient (Note these primary CNS lymphomas are in addition to those involved by the systemic lymphomas).\n\n\nBody cavity based\xa0lymphoma\n\n\nRare\n\n\nHas an unusual distribution\n\n\nIt grows exclusively in body cavities in the form of pleural peritoneal and pericardial effusions', 'role': 'assistant'}]