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: Dental
[{'content': 'Inflammation of the perapical tissue is sustained by which of the following \nSelect and explain. \nA. Stagnant tissue fluid, B. Necrotic tissue, C. Microorganisms, D. Pus cells', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]