This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vesiculobullous (Blistering) Disorders, Subject name: Skin
[{'content': 'Row of tombstone is seen in which skin disorder: \nSelect and explain. \nA. Pemphigus vulgaris, B. Pemphigus foliaceous, C. Paraneoplastic pemphigus, D. Bullous pemphigoid', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. A. Pemphigus vulgaris* Pemphigus vulgaris is characterized by following signs:1. Bulla spread sign2. Perilesional, and distant Nikolsky sign3. Tzanck smear: Acantholytic cell* Histopathology shows suprabasal blister with row of tomb stone appearance of basal cells.* Direct immunofluorescence from perilesional skin demonstrated intra epidermal IgG deposits' in a fishnet pattern.", 'role': 'assistant'}]