Which of the following is correctly matched?

• A
  $[Fe(CN)_6]^{4-}$ and $[Fe(CN)_6]^{3-}$ $-$ both are octahedral and diamagnetic with $d^2sp^3$ hybridisation
• B
  $Ni(CO)_4$ and $[Ni(CN)_4]^{2-}$ $-$ both are tetrahedral and diamagnetic with $sp^3$ hybridisation
• C
  $Ni(CO)_4$ and $[Co(CO)_4]^{-}$ $-$ both are tetrahedral and diamagnetic
• D
  $[Co(H_2O)_6]^{3+}$ and $[Cr(H_2O)_6]^{3+}$ $-$ both are paramagnetic and metal is $d^2sp^3$ hybridised