which choice best corrects the verb tense error

A. for the upcoming bake sale at the fair, we bake the cake and frosted it.
B. for the upcoming bake sale at the fair, we baked the cake and had frosted it.
C. for the upcoming bake sale at the fair, we baked the cake and frosted.
D. for the upcoming bake sale at the fair, we will have baked the cake and frost it.