Which of the following statements is false with respect to cost behavior? A. Mixed costs include a fixed and variable portion of the cost. OB. Cost behavior relates to the categorization of costs as fixed, variable, or mixed. OC. Fixed costs, calculated on a per unit basis, are inversely related to the change in activity level. D. Variable costs do not change in total as activity levels change. E. Knowledge of cost behavior is not required when preparing a traditional income statement.