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: Microbiology
[{'content': 'IFN-β is secreted by \nSelect and explain. \nA. Leucocytes, B. Fibroblasts, C. Nk cells, D. Macrophage', 'role': 'user'}, {'content': 'Answer: B \nExplanation: IFN-α - Leucocytes.\nIFN-β - Fibroblasts.\nIFN-γ -\xa0 T4 and Tc cells, Nk cells.', 'role': 'assistant'}]