<prompt> Which of the following is wrong statements:Koilonychia in Vit B12 deficiencyOncholysis in PsoriasisMees lines in Arsenic poisoningPterygium of nailis in Lichen Planus  <response>: Ans: A i.e. Koilonychia in Vit B12 deficiency. Koilonychia Spoon nail The nail is concave with raised edges. Seen in Iron Deficiency Anemia,Hypothyroidism,Lichen Planus. 