Which of the following is a major problem associated with the percentage-of-sales method?

 A. It reverses the cause-and-effect relationship between advertising and sales. 

B. It is financially unsafe. 

C. It is extremely tough to implement. 

D. It is used only by firms that do not understand the role of advertising and promotions. 

E. It has no theoretical basis, and the budgetary amount is often set using a flat rate.