This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autoimmune skin disorders, Subject name: Dental
All of the following may lead to plaque formation except 
Select and explain. 
A. Pityriasis rosea, B. Psoriasis, C. Pemphigus, D. Lichen planus
C: Pemphigus
Answer: C: Pemphigus 
Explanation: Pemphigus vulgaris is a immunobullous disorder characterised by formation of flaccid blisters in skin and mucous membranes. other options lesions are characterised by papules and plaques. iadvl textbook of dermatology page 1088