German silver does not have silver in it,its composition is

Question

$ (a)\;\text{ Copper 35%,zinc 25% and Ni 55%} \\(b)\;\text {Copper 45%,zinc 25% and Ni 20%} \\(c)\;\text{Copper 50%,zinc 19% and Ni 30%} \\ (d)\;\text{Copper 25%,zinc 25% and Ni 50%} $