When the Following Oxidation-Reduction Reaction in Basic Solution Is Balanced,what

Multiple Choice

When the following oxidation-reduction reaction in basic solution is balanced,what is the lowest whole-number coefficient for OH^-,and on which side of the balanced equation should it appear?
Cr₂O₃(s) → Cr(OH) ₂(aq) + CrO₄^2-(aq)

A) 2,reactant side
B) 10,product side
C) 4,product side
D) 4,reactant side
E) 2,product side