Which one among the following elements/ions is essential in small quantities for development of healthy teeth but causes mottling of the teeth if consumed in higher quantities?

Q. Which one among the following elements/ions is essential in small quantities for development of healthy teeth but causes mottling of the teeth if consumed in higher quantities?

A.            Iron

B.            Chloride

C.            Fluoride

D.            Potassium

Answer: Fluoride