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
Which of the following is/are not the cause of hypopigmentation: 
Select and explain. 
A. Leprosy, B. Pinta, C. Syphilis, D. None
D: None
Answer: D: None 
Explanation: D i.e. None