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': 'The best way of detecting the presence of viruses in the infected cell culture is: \nSelect and explain. \nA. Cytopathic changes in culture cells, B. Presence of viral protein in the infected monolayer, C. Haemagglutination test, D. Haemagglutination inhibition test', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The changes in cell morphology caused by infecting virus are called cytopathic effects (CPE).\nIn order to view these cellular changes under light microscopy, the cell cultures have been stained with hematoxylin, a basic dye, and eosin, an acidic dye.\xa0\nCommon examples are rounding of the infected cell, fusion with adjacent cells to form a syncytia (polykaryocytes), and the appearance of nuclear or cytoplasmic inclusion bodies.', 'role': 'assistant'}]