This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Psoriasis, Subject name: Dental
All are nail changes seen in cases of psoriasis except: 
Select and explain. 
A. Subungual hyperkeratosis, B. Thimble pitting, C. Mees lines, D. Oil drop sign
C: Mees lines
Answer: C: Mees lines 
Explanation: Mees lines - seen in Arsenic poisoning Nail changes in psoriasis - MC - Nail pitting/Thimble pitting Most characteristic - oil drop sign/ salmon patch Onycholysis Leukonychia Subungual hyperkeratosis Nail tunnel