Which of the following is the strongest reducing agent?

Which of the following is only a redox reaction but not a disproportionation reaction?

Which of the following are disproportionation reactions?

(A) $\mathrm{Cl}_2+2 \mathrm{NaOH} \longrightarrow \mathrm{NaCl}+\mathrm{NaOCl}+\mathrm{H}_2 \mathrm{O}$

(B) $\mathrm{H}_2 \mathrm{O}_2 \longrightarrow 2 \mathrm{H}_2 \mathrm{O}+\mathrm{O}_2$

(C) $2 \mathrm{KMnO}_4 \rightarrow \mathrm{~K}_2 \mathrm{MnO}_4+\mathrm{MnO}_2+\mathrm{O}_2$

(D) $3 \mathrm{MnO}_4^{2-}+4 \mathrm{H}^{+} \longrightarrow 2 \mathrm{MnO}_4^{-}+\mathrm{MnO}_2+2 \mathrm{H}_2 \mathrm{O}$