Which of the following is not an assumption of CVP analysis?

Select one:

A$.$

The sales mix ratio $($for multiple products$)$ remains constant.

B$.$

Total fixed cost and total variable cost per unit are constant over the entire range of analysis.

C$.$

Sales price will remain constant on a per$-$unit basis regardless of the level of sales.

D$.$

All costs are variable in the relevant range.

E$.$

All of the above