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
A 40-year male presenting with painful flaccid vesicles on the face and oral mucosa with asymmetric distribution. Immunofluorescence shows intercellular IgG deposition in the epidermis. Diagnosis is – 
Select and explain. 
A. Erythema multifomiis, B. Bullous pemphigoid, C. Pemphigus vulgaris, D. Herpes zoster
C: Pemphigus vulgaris
Answer: C: Pemphigus vulgaris 
Explanation: In this patient (go stepwise)


No itching
Pain present (only two differentials, i.e. pemphigus and herpes zoster)
Flaccid vesicles on face
Mucosal involvement
Asymmetric distribution
Intercellular IgG in the epidermis


Diagnosis is pemphigus vulgaris