Both $$[Ni(CO)_4]$$ and $$[Ni(CN)_4]^{2-}$$ are diamagnetic. The hybridisations of nickel in these complexes, respectively, are

A

$$sp^3, sp^3$$

B

$$sp^3, dsp^2$$

C

$$dsp^2, sp^3$$

D

$$dsp^2, dsp^2$$