In basic medium, $\mathrm{H}_2 \mathrm{O}_2$ exhibits which of the following reactions?
(A) $\mathrm{Mn}^{2+} \rightarrow \mathrm{Mn}^{4+}$
(B) $\mathrm{I}_2 \rightarrow \mathrm{I}^{-}$
(C) $\mathrm{PbS} \rightarrow \mathrm{PbSO}_4$
Choose the most appropriate answer from the options given below :