Select the correct order for the wavelength of absorption for the given complexes:

Since the crystal field splitting will be bigger and the wavelength of light absorbed will be less the stronger the ligand then the correct order for the wavelength of absorption for the given complexes is, 

${\left[{\mathrm{CrCl}}_6\right]}^{3-}>{\left[\mathrm{Cr}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}>{\left[\mathrm{Cr}{\left({\mathrm{NH}}_3\right)}_6\right]}^{3+}>{\left[\mathrm{Cr}(\mathrm{CN}{)}_6\right]}^{3-}$

${\mathrm{\Delta }}_0\propto \frac{1}{\lambda }$

Hence, option B is correct.