What Is the Molar Solubility of Barium Carbonate in Pure

What is the molar solubility of barium carbonate in pure water? (Ksp = 5.1 × 10^-9)

A) 5.1 × 10^-9 M
B) 7.1 × 10^-5 M
C) 1.1 × 10^-3
D) 1.7 × 10^-3
E) 2.6 × 10^-17