Oxide ions with ions of metals A and B together form a crystal. The oxide ions get organized into a cubic closed packed (ccp) lattice. In the oxide lattice, the metal ion A occupies 25% of the octahedral voids and the metal ion B occupies 50% of the tetrahedral voids. Oxidation states of A and B respectively are

A

$$+3, +1$$

B

$$+4, +1$$

C

$$+1, +3$$

D

$$+2, +4$$