Calculate $\Delta$ G^o for the Following Reaction at 25 ^oC And $\Delta$

Calculate $\Delta$ G^o for the following reaction at 25 ^oC and $\Delta$ S=0

A) -10 kcal/mol
B) 10 kcal/mol
C) 34 kcal/mol
D) -34 kcal/mol
E) None of the above.