What occurs as a result of disproportionation?

Disproportionation is a specific type of redox reaction where a single substance undergoes both oxidation and reduction simultaneously. This is unique because, in such a reaction, one part of the molecule is oxidized, meaning it loses electrons and typically increases in oxidation state, while another part is reduced, which means it gains electrons and decreases in oxidation state.

For example, consider chlorine in a disproportionation reaction. In a reaction involving Cl2, some chlorine atoms are oxidized to ClO3- (gaining an oxidation state of +5) while others are reduced to Cl- (having an oxidation state of -1). This dual action of oxidation and reduction taking place on the same substance defines the process of disproportionation, making it an essential concept in understanding redox chemistry.

The inclusion of neutralization of acids and bases does not pertain to disproportionation as it involves an acid reacting with a base to form a salt and water, lacking the electron transfer characteristic seen in oxidation and reduction processes. Similarly, stating that only oxidation or only reduction occurs misses the critical aspect of how disproportionation functions, thus reinforcing the unique combinatory action depicted in the correct answer.