Which of the following statements is/are not correct ${\mathrm{CCl}}_3^{-}$ and ${\mathrm{CCl}}_2$ ?

The following statements is/are not correct about  ${\mathrm{CCl}}_3^{-}$ and ${\mathrm{CCl}}_2$: Back bonding in ${\mathrm{CCl}}_3^{-}$ and from C to Cl, but reverse in: ${\mathrm{CCl}}_2$. The direction of back bonding is just opposite in two cases.

Hence, the correct option is C,D.