Calcium fluoride, CaF2, has a molar solubility of 2.1 x 10^-4 mol/L at pH = 7.00. By what factor does its molar solubility increase in a solution with pH = 3.00? The pKa of HF is 3.17
(A) 1.48
(B) 1.83
(C) 2.48
(D) 4.96