Fusion of $$MnO_2$$ with KOH in presence of $$O_2$$ produces a salt W. Alkaline solution of W upon electrolytic oxidation yields another salt X. The manganese containing ions present in W and X, respectively, are Y and Z. Correct statement(s) is (are)

A

In aqueousacidic solution, Y undergoes disproportionation reaction to give Z and $$MnO_2$$

B

Both Y and Z are coloured and have tetrahedral shape

C

Y is diamagnetic in nature while Z is paramagnetic

D

In both Y and Z, $$\pi-$$bonding occurs between p-orbitals of oxygen and d-orbitals of manganese