Square planar complexes are generally formed by `d^(8)` ions with strong field ligands. The crystal field splitting is larger for second and third row transition elements and for more highly charged species. All the complexes having `4d^(8)" and "5d^(8)` configuration are mostly square including those with weak field ligands such halide ions. Square planar complexes with coordination number four can show diastereoisomerism.
Amongst the following complexes which has square planar geometry ?

Options

A. `[RhCl(CO)(PPh_(3))_(2)]`
B. `K_(3)[Cu(CN)_(4)]`
C. `K_(2)[Zn(CN)_(4)]`
D. `[Ni(CO)_(4)]`

Answer

A