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': 'In early AIDS infection of ELISA is negative what should be done - \nSelect and explain. \nA. p24 antibody, B. gp 120 antibody, C. gp 120 antigen, D. p 24 antigen', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]