Which species among the following does not show disproportionation reactions?

Which of the following reactions are disproportionation reactions?
$(a)$ $2 Cu^{+} \rightarrow Cu^{2+} + Cu^{0}$
$(b)$ $3 MnO_{4}^{2-} + 4 H^{+} \rightarrow 2 MnO_{4}^{-} + MnO_{2} + 2 H_{2}O$
$(c)$ $2 KMnO_{4} \xrightarrow{\Delta} K_{2}MnO_{4} + MnO_{2} + O_{2}$
$(d)$ $2 MnO_{4}^{-} + 3 Mn^{2+} + 2 H_{2}O \rightarrow 5 MnO_{2} + 4 H^{+}$
Select the correct option from the following:

Which of the given reactions is not an example of a disproportionation reaction?

Which one of the following is a disproportionation reaction?

Which of the following best describes the behavior of bromine in the reaction given below?
$H_2O + Br_2 \to HOBr + HBr$

Which of the following does not show a disproportionation reaction?