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: Skin
Wrong statement is: 
Select and explain. 
A. Mees line in Arsenic poisoning, B. Pterygium of nails in Lichen Planus, C. Oncholysis in Psoriasis, D. Koilonychia in Megaloblastic Anemia (B12 def.)
D: Koilonychia in Megaloblastic Anemia (B12 def.)
Answer: D: Koilonychia in Megaloblastic Anemia (B12 def.) 
Explanation: D i.e. Koilonychia in megaloblastic anemia (B12 def)