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: Pathology
[{'content': 'The pathogenesis of periapical cyst is? \nSelect and explain. \nA. Increased pressure within the cyst, B. Immune mediated bone destruction, C. Proliferation of epithelium, D. None', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]