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': "Widening of periodontal ligament is seen in: \nSelect and explain. \nA. Hypercementosis, B. Osteosarcoma, C. Hypofunction of teeth, D. Paget's disease", 'role': 'user'}, {'content': "Answer: B \nExplanation: Widening of periodontal ligament is seen in\n\nOsteosarcoma\nChondrosarcoma\nScleroderma\nTrauma from occlusion\n\nObliteration of periodontal ligament space is seen in\n\nHypercementosis\nAnkylosis\nHypofunction of teeth\nPaget's disease", 'role': 'assistant'}]