The structure of ${\mathrm{ICl}}_2^{+}$ would be :

The deformed trigonal pyramidal structure of ${\mathrm{ICl}}_2^{-}$. The ${\mathrm{sp}}^3\mathrm{d}-$hybridized state of ${\mathrm{ICl}}_2^{-}$ is deformed due to the existence of a lone pair of electrons on the I-atom, despite possessing a trigonal bipyramidal structure.

Hence, the option D is correct.