This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vestibulobullous disorders, Subject name: Dental
[{'content': 'Drug induced pemphigus is most commonly caused by \nSelect and explain. \nA. Penicillamine, B. Phenytoin sodium, C. Carbamazepine, D. Penicillin', 'role': 'user'}, {'content': "Answer: A \nExplanation: captopril and d- penicillamine are the two most common drugs inducing pemphigus vulgaris . page no.281 . Reference IADVL's concise textbook of dermatology", 'role': 'assistant'}]