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
Characteristic feature of pemphigus vulgaris: 
Select and explain. 
A. Sub epidermal bullae, B. Acantholysis, C. Negative Nikolsky's sign, D. Bullae on erythematous base
B: Acantholysis
Answer: B: Acantholysis 
Explanation: Ans. b. AcantholysisSubepidermal bullae on erythematous base with negative Nikolsky sign is seen in bullous pemphigoid