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': 'A 40-year male presenting with painful flaccid vesicles on the face and oral mucosa with asymmetric distribution. Immunofluorescence shows intercellular IgG deposition in the epidermis. Diagnosis is – \nSelect and explain. \nA. Erythema multifomiis, B. Bullous pemphigoid, C. Pemphigus vulgaris, D. Herpes zoster', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In this patient (go stepwise)\n\n\nNo itching\nPain present (only two differentials, i.e. pemphigus and herpes zoster)\nFlaccid vesicles on face\nMucosal involvement\nAsymmetric distribution\nIntercellular IgG in the epidermis\n\n\nDiagnosis is pemphigus vulgaris', 'role': 'assistant'}]