This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skin, Subject name: Medicine
[{'content': 'A 70-year-old man comes to the emergency department because of a skin rash and severe itching. He appears ill; there is a generalized skin rash that is scaly, erythematous, and thickened. His palms, soles, and scalp are also involved. Which of the following is the most likely diagnosis? \nSelect and explain. \nA. pemphigus vulgaris, B. rosacea, C. erythroderma (exfoliative dermatitis), D. dermatitis herpetiformis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Exfoliative dermatitis is a rare skin condition, but because of its severity, patients with this syndrome are often admitted to a hospital. The syndrome can be primary, appearing in otherwise healthy individuals, or secondary to malignancy, contact dermatitis, drugs, or other dermatologic diseases (e.g., psoriasis). Even mild cases require systemic treatment for the severe itching. Antihistamines are usually the first choice.', 'role': 'assistant'}]