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
Acantholysis is seen in all of the following except – a) Pemphigusb) Bullous pemphigoidc) Steven–Johnson syndromed) Toxic epidermal necrolysis 
Select and explain. 
A. ab, B. ad, C. cd, D. bd
D: bd
Answer: D: bd 
Explanation: None