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': 'Which of the following best denotes classical complement pathway activation in immunoinfiammatory condition - \nSelect and explain. \nA. C\n2\n, C\n4\n, C\n3\n decreased, B. C\n2\n and C\n4\n normal, C\n3\n is decreased, C. C\n3\n normal and C\n2\n C\n4\n decreased, D. C\n2\n, C\n4\n, C\n3\n all are elevated', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]