Pick out the correct statement with respect to $[Mn(CN)_6]^{3-}$

Question

( A ) It is $dsp^2$ hybridised and square planar
( B ) It is $sp^3d^2$ hybridised and tetrahedral
( C ) It is $d^2 sp^3$ hybridised and octahedral
( D ) It is $sp^3d^2$ hybridised and octahedral