Indicate the complex ion which shows geometrical isomerism:

${\left[\mathrm{Cr}{\left({\mathrm{H}}_2\mathrm{O}\right)}_4{\mathrm{Cl}}_2\right]}^{+}$ shows geometrical isomerismm as trans and cis.

Chemical species known as geometric isomers have the same kind and number of atoms as another species but a distinct geometric structure.

Hence, option A is correct.