Select the nature or type of redox change in the following reaction:-

${\mathrm{C}\mathrm{l}}_2\to \mathrm{ }{\mathrm{C}\mathrm{l}\mathrm{O}}^{-}\mathrm{ }+\mathrm{ }{\mathrm{C}\mathrm{l}}^{-}$

Auto-redox or disproportionation is the one in which same substance is oxidized and reduced as well.

Intramolecular redox change is the one in which one element of a compound is oxidized and the other element is reduced.

Intermolecular redox is the one in which one of the two reactants is oxidized and the other is reduced.