Three complexes, [ CoCl ( NH_3)_5]^2+ (I), [ Co ( NH_3)_5 H_2 O ]^3+ (II) and [ Co ( NH_3)_6]^3+ (III) absorb light in the visible region. The…

Three complexes, $$\begin{aligned} & {\left[\mathrm{CoCl}\left(\mathrm{NH}_3\right)_5\right]^{2+} \text { (I), }} \\ & {\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{H}_2 \mathrm{O}\right]^{3+} \text { (II) and }} \\ & {\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right]^{3+} \text { (III) }} \end{aligned} $$ absorb light in the visible region. The correct order of the wavelength of light absorbed by them is :