Correct Answer - D
`K_(3)[Fe(CN)_(6)]`
Electronic configuration of `Fe=[Ar]4s^(2)3d^(6)`
Electronic configuration of `Fe^(+3)= [Ar]3d^(5)`
Number of ligand ( coordination number ) `=6`
Nature of ligand is strong field.
Hybridization of Fe is `d^(2) sp^(3)`.