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: Pathology
Mottled enamel is due to: 
Select and explain. 
A. Vitamin A deficiency, B. Excess of fluoride, C. Vitamin D deficiency, D. Teratogens
B: Excess of fluoride
Answer: B: Excess of fluoride 
Explanation: None