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: Pathology
[{'content': 'Multiple myleoma is characterized by all except \nSelect and explain. \nA. Presence of light chains, B. Monoclonal gammopathy, C. Polyclonal gammopathy, D. Hypergammaglobulinemia', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]