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
Polygonal violaceous , well defined flat topped ,itchy papules are the primary lesions of 
Select and explain. 
A. Lichen planus, B. Phemphigus vulgaris, C. Lupus erythematous, D. Psoriasis
A: Lichen planus
Answer: A: Lichen planus 
Explanation: Lichen planus lesions are classically violaceous well defined polygonal itchy papules.