At `25^(@)`C, `K_(sp)` for `PbBr_(2)` is equal to `8xx10^(-5)`. If the salt is `80%` dissociated, What is the solubility of `PbBr_(2)` in mol//litre?
A. `[(10^(-4))/(1.6 xx 1.6)]^(1//3)`
B. `[(10^(-5))/(1.6 xx 1.6)]^(1//3)`
C. `[(10^(-4))/(0.8 xx 0.8)]^(1//3)`
D. `[(10^(-3))/(1.6 xx 1.6)]^(1//2)`