Which of the following statements is correct for a solution saturated with `AgCl` and `AgBr` if their solubilities in moles per litre in separate solutions are `x` and `y` respectively?
A. `[Ag^(+)]=[Br^(-)]xx[Cl^(-)]`
B. `[Cl^(-)]gt[Br]`
C. `[Br^(-)]lty`
D. `[Ag^(+)]=x+y`