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': 'Dense mass of connective tissue seen in endodontically treated teeth called as: \nSelect and explain. \nA. Periapical cyst, B. Periapical granuloma, C. Residual cyst., D. Periapical scar.', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]