This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'The following diagnostic tests are useful for corresponding purposes except \nSelect and explain. \nA. Ziehl-Neelsen staining - Detection of mycobacteria, B. Immunoflorescence - Detection of Influenza virus, C. Specific IgM antibodies - Immunity against Rubella, D. Specific IgM antibodies - Detection of acute infection', 'role': 'user'}, {'content': 'Answer: C \nExplanation: IgM antibody appears following an acute infection. It is not specific for a disease. Ref: Baveja textbook of microbiology; 4th edition', 'role': 'assistant'}]