Paramagnetism Questions

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:

The $d$ -electron configurations of ${\text{Cr}}^{2+}$, ${\text{Mn}}^{2+}$, ${\text{Fe}}^{2+}$ and ${\text{Ni}}^{2+}$ are $3d^4$, $3d^5$, $3d^6$ and $3d^8$ respectively. Which one of the following aqua complexes will exhibit the minimum paramagnetic behaviour?

Which of the following complexes exhibits the highest paramagnetic behaviour?(At. number $\text{Ti}=22,\text{V}=23,\text{Fe}=26,\text{Co}=27$)

Which of the following complex compounds will exhibit highest paramagnetic behaviour?

Which of the following is paramagnetic?