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
Nikolsky's sign is positive in 
Select and explain. 
A. Pemphigus, B. Dermatitis herpatiformis, C. Pemphigoid, D. Rubella
A: Pemphigus
Answer: A: Pemphigus 
Explanation: None