Banner Company produces 5 products. If the variable cost of one product increases, and using the assumptions made in the text about multiproduct cost volume profit analysis, the effect of this change on the breakeven quantities required for Banner Company to breakeven will:

a. This question cannot be answered without more information

b. Require that the sales of that product increase while the sales of the other products remain constant

c. Require that the sales of that product increase while the sales of the other products decrease

d. Require that the sales of all products increase