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
A 5 year boy has recurrent multiple asymptomatic oval and circular faintly hypopigmented macules with fine scaling on his face. The most probable clinical diagnosis is: 
Select and explain. 
A. Ptyriasis versicolor, B. Indeterminate leprosy, C. Ptyriasis alba, D. Acrofacial vitiligo
C: Ptyriasis alba
Answer: C: Ptyriasis alba 
Explanation: C i.e. Ptyriasis alba