(A): Concentration of soluble `F^(-)` ions in drinking water about 1 ppm is essential.
(R) Enamel on teeth is made much harder by converting hydroxyapatile `3Ca_(3)(PO_4)_2Ca(OH)_2` into `3Ca_(3)(PO_4)_2 CaF_2`

Options

A. Both (A) and (R) are true and (R) is the correct explanation of (A)
B. Both (A) and (R) are true and (R) is not the correct explanation of (A)
C. (A) is true but (R) is false
D. (A) is false but (R) is true

Answer

A