Octahedral complexes of copper $\left(\mathrm{II}\right)$ undergo structural distortion (Jahn-Teller). Which one of the given copper $\left(\mathrm{II}\right)$ complexes will show the maximum structural distortion?
(en-ethylenediamine; ${\mathrm{H}}_2\mathrm{N}-{\mathrm{CH}}_2-{\mathrm{CH}}_2-{\mathrm{NH}}_2$)

Sum of oxidation state (magnitude) and coordination number of cobalt in $\mathrm{Na}\left[\mathrm{Co}\left(\mathrm{bpy}\right){\mathrm{Cl}}_4\right]$ is

The number of paramagnetic species from the following is

${\left[\mathrm{Ni}(\mathrm{CN}{)}_4\right]}^{2-},\left[\mathrm{Ni}(\mathrm{CO}{)}_4\right],{\left[{\mathrm{NiCl}}_4\right]}^{2-}$

${\left[\mathrm{Fe}(\mathrm{CN}{)}_6\right]}^{4-},{\left[\mathrm{Cu}{\left({\mathrm{NH}}_3\right)}_4\right]}^{2+}$

${\left[\mathrm{Fe}(\mathrm{CN}{)}_6\right]}^{3-}\text{ and }{\left[\mathrm{Fe}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{2+}$

Match List I with List II

Choose the correct answer from the options given below :-