Which of the following are paramagnetic?A. $[NiC{l}_4{]}^{2-}$ B. $Ni(CO{)}_4$ C. $[Ni(CN{)}_4{]}^{2-}$ D. $[Ni(H_{2}O{)}_6{]}^{2+}$ E. $Ni(PP{h}_3{)}_4$ Choose the correct answer from the options given below:

1. $Ni$ has $3d^{8}4s^2$ configuration. $N{i}^{2+}$ is $3d^8$.2. A. $[NiC{l}_4{]}^{2-}$: $C{l}^{-}$ is weak field ligand. Tetrahedral, $s{p}^3$ hybrid. 2 unpaired electrons. Paramagnetic.3. B. $Ni(CO{)}_4$: $Ni$ in zero state. $CO$ is strong field. Electrons pair up. Diamagnetic.4. C. $[Ni(CN{)}_4{]}^{2-}$: $C{N}^{-}$ is strong field. Square planar. Electrons pair up. Diamagnetic.5. D. $[Ni(H_{2}O{)}_6{]}^{2+}$: $H_{2}O$ is weak field. Octahedral. 2 unpaired electrons in $e_g$ orbitals. Paramagnetic.6. E. $Ni(PP{h}_3{)}_4$: $Ni$ in zero state. Diamagnetic.Paramagnetic species are A and D.