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
Nail pitting is caused by all except ? 
Select and explain. 
A. Lichen planus, B. Hypehyroidism, C. Fungal infection, D. Pityriasis Rosacea
D: Pityriasis Rosacea
Answer: D: Pityriasis Rosacea 
Explanation: Ans. is 'd' i.e., Pityriasis Rosacea