Which one among the following pair of ions cannot be separated by `H_(2)S` in dilute hydrochloric acid?

Options

A. `Bi^(3+),Sn^(4+)`
B. `Al^(3+),Hg^(2+)`
C. `Zn^(2+),Cu^(2+)`
D. `Ni^(2+),Cu^(2+)`

Answer

A

Explanation

`Bi^(3+),Sn^(4+)` both belong to group II of basic radicals.