Select the pair of hydrate isomers in which both hydrate isomers have two stereoisomeric form :

$\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_4\left({\mathrm{H}}_2\mathrm{O}\right)\mathrm{Cl}\right]{\mathrm{Cl}}_2$ and $\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_4{\mathrm{Cl}}_2\right]{\mathrm{Cl}}_2\mathrm{O}$ pair of hydrate isomers in which both hydrate isomers have two stereoisomeric form

So, option C is correct.