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': '30 years old male presents with painful flaccid bullae on right face and oral mucosa without evidence of inflammation or redness; what is the most probable diagnosis? \nSelect and explain. \nA. Pemphigus vulgaris, B. Pemphigus foliaceous, C. Bullous pemphoid, D. Dermatitis herpetiformis', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Pemphigus vulgaris", 'role': 'assistant'}]