The manganate and permanganate ions are tetrahedral, due to

• A

  the $\mathrm{\pi }$ -bonding involves overlap of d -orbitals of oxygen with d -orbitals of manganese

• B

  the $\mathrm{\pi }$ -bonding involves overlap of p -orbitals of oxygen with d -orbitals of manganese

• C

  there is no $\mathrm{\pi }$-bonding

• D

  the $\mathrm{\pi }$ -bonding involves overlap of p -orbitals of oxygen with p -orbitals of manganese.