With Regard to the Full Costs Versus Contribution Margin Controversy

With regard to the full costs versus contribution margin controversy, which of the statements below is incorrect?

A) under the full costs (or net profit) approach, all cost must be assigned in order to determine actual profit
B) The contribution margin approach claims that only costs that are controllable and traceable to a particular segment should be subtracted from the revenue produced by that segment
C) In marketing costs analysis, the trend factors the full-cost approach
D) With the contribution margin approach, costs are classified as either variable or fixed, then all the variable costs are deducted from sales to determine a given segment's contribution margin