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: Skin
[{'content': 'False regarding acanthosis nigricans is \nSelect and explain. \nA. Prognostic indicator, B. Velvety plaques on diy hyperpigmentation, C. Confirmatory sign of malignancy, D. Gastric adenocarcinma is commonest malignant association', 'role': 'user'}, {'content': 'Answer: C \nExplanation: C. i.e. Confirmatory sign of malignancy', 'role': 'assistant'}]