Answer:
Option A,C,D
Explanation:
In neutral medium ; $MnO_{4}^{-} \rightarrow MnO_{2} (Mn^{7+} +3e^{-} \rightarrow Mn^{4+})$
In alkaline medium : $MnO_{4}^{-} \rightarrow MnO_{2} (Mn^{7+}+3e^{-} \rightarrow Mn^{4+})$
In acidic medium: $Mn_{4}^{-} \rightarrow Mn^{2} (Mn^{7+}+5e^{-} \rightarrow Mn^{2+})$
