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: Social & Preventive Medicine
[{'content': 'In diagnosis of AIDS, criteria include the following except -a) CD4 <200b) CD8 < 500c) CD 4 : CD 8 = 1d) Presence of any of the opportunistic infections tuberculosis,pneumosystic carinii, cytomegaloviruse) Western blot is positive \nSelect and explain. \nA. ab, B. bc, C. acd, D. bce', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]