The correct option is D disproportionation reaction
The reaction 3ClO(aq)−→ClO3(aq)−+2Cl(aq)− is an example of disproportionation reaction.
In this reaction, chlorine is oxidized as well as reduced.
The oxidation states of chlorine in ClO(aq)−,ClO3(aq)− and Cl(aq)− are +1,+5 and −1 respectively.