(A-q), (B-q) , (-s), (D-r)
(A) `dsp^(2)` hybridisation, Au is in +3 oxidation state and complex is diamanetic. (5`d^(8)` configureation)
(B) `sp^(3+)` hybridisation, Cu is in +1 oxidation state and complex is diamagnetic. `NC^(-)` is strong field ligand but no empty d-orbirtal is avaliable for `dsp^(2)` hybridisation.
( C) `sp^(3)d^(2)` hydridisation : Co is in +2 oxidation state anc complex is paramagnetic with one unpaired electron.
(D) `d^(2)sp^(3)` hybridisation with Fe in +1 oxidation state and paramagnetic with three unpaied electron
