In which of the following solutions, the solubility of AgCN will be greater than that in pure water?
(Given : `K_(sp)(AgCN)4xx10^(-16),K_(a)(HCN)=5xx10^(-10)`)
A. `0.01MAgNO_(3)` solution
B. A buffer solution of pH=12
C. 0.2M `NH_(3)` solution
D. A buffer solution of pH=5