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': 'Malignant form of intraoral acanthosis nigricans is associated with: \nSelect and explain. \nA. Internal malignancy, B. External malignancy, C. Both 1 & 2, D. None of the above', 'role': 'user'}, {'content': "Answer: A \nExplanation: Acanthosis nigricans is an acquired dermatologic problem characterized by the development of a velvety, brownish alteration of the skin. In some instances, this unusual condition develops in conjunction with a malignancy, usually gastrointestinal cancer, and is termed malignant acanthosis nigricans. The cutaneous lesion itself is benign, yet it is significant because it represents a cutaneous marker for internal malignancy.\nRef: Neville's\xa0 oral and maxillofacial pathology 4th edition page 748", 'role': 'assistant'}]