Which of the following is incorrect with regard to short-term decision making? A. Variable costs and fixed costs should be computed on a per unit basis so it will be easier to analyze effects on operating income at various quantity levels. B. A manager should only focus on relevant information, which could include both financial and nonfinancial information. C. Unitized fixed costs can be misleading in the decision-making process because they appear to behave as variable costs. D. Variable and Fixed costs must be analyzed separately using the contribution margin approach. E. Short-term decisions typically pertain to decisions made within one year