If the K_sp for AgCl Is Equal to 4 $\mathrm { AgCl } _ { 2 } ^ { - }$

If the K_sp for AgCl is equal to 4.65×10^-9 and the K_f for $\mathrm { AgCl } _ { 2 } ^ { - }$ is equal to 8.7×10⁵ at $35 ^ { \circ } \mathrm { C }$ , what is the solubility of AgCl in 1.0 M KCl solution, ignoring the formation of any complex ions?

A) 3.24×10^-10M
B) 6.82×10^-9M
C) 4.67×10^-10M
D) 9.65×10^-9M
E) 4.65×10^-9M