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: Surgery
[{'content': 'Following are seen in fibrous dysplasia EXCEPT September 2004 \nSelect and explain. \nA. Cafe-au-lait spots, B. No premalignant change, C. Expanding rib lesions, D. Expanding lesions of maxilla', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B i.e. No premalignant change', 'role': 'assistant'}]