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': 'A patient presented with arthritis and purpura. Laboratory examination showed monoclonal and polyclonal cryoglobulins. Histopathology showed deposits of cryoglobulins around the vessels. The patient should be tested for which of the following? \nSelect and explain. \nA. HBV, B. HCV, C. EBV, D. Parvovious', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]