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': 'Following are signs of internal malignancy except – \nSelect and explain. \nA. Tuberous sclerosis, B. Acanthosis nigricans, C. Clubbing, D. Dermatomyositis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Acanthosis nigricans, clubbing and dermatomyositis are paraneoplastic cutaneous signs of internal malignancy.', 'role': 'assistant'}]