In partitioning variance in a balanced factorial ANOVA, we can conclude that: a. the main effects of A and B and the AxB interaction are independent of one another b. factors A and B may be correlated as long as they are not correlated with the AxB interaction. c. factors A and B are not correlated with one another but each may be correlated with the interaction. d. all variance in the model is accounted for by factors A and B.