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: Pathology
Subepithelial bulla is: 
Select and explain. 
A. Herpes zoster., B. Pemphigus., C. Bullous pemphigoid., D. Hailey Hailey disease.
C: Bullous pemphigoid.
Answer: C: Bullous pemphigoid. 
Explanation: None