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': 'Phrynoderma is a cutaneous manifest-ation of severe deficiency of vitamin : \nSelect and explain. \nA. A, B. B, C. C, D. D', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. A', 'role': 'assistant'}]