Fusion of $Mn{O}_2$ 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) about Y & Z is/are

In aqueous acidic solution, ‘Y’ undergoes disproportionation reaction to give Z and $Mn{O}_2$

‘Y’ is diamagnetic in nature while ‘Z’ is paramagnetic

Both Y and Z are coloured and have tetrahedral shape

In both Y and Z, π bonding occurs between p-orbitals of oxygen and d-orbitals of Manganese