Number of incorrect statements are‐
$\left(\mathrm{A}\right)$ The $\mathrm{\pi }$ bond between metal and carbonyl carbon reduces the bond order of $\mathrm{C}-\mathrm{O}$ in carbon monoxide
($\mathrm{B})\mathrm{}\mathrm{d}{\mathrm{z}}^2$ orbital of central metal atom/ ion is used in $\mathrm{d}\mathrm{s}{\mathrm{p}}^2$ hybridisation.
$\left(\mathrm{C}\right)\mathrm{}\mathrm{C}{\mathrm{N}}^{-}$ is a $\mathrm{\pi }‐$ acid Ligand.
$\left(\mathrm{D}\right)\mathrm{}$ All negative ligands are stronger than neutral ligands.