What Is the Greatest Shortcoming of the Percentage of Sales

What is the greatest shortcoming of the percentage of sales method for setting the advertising budget?

A) The percentage of sales method is too expensive to be used by small business owners.
B) The basis for setting the percentage is often determined arbitrarily.
C) The percentage of sales method assumes a certain number of dollars are needed to sell a certain number of units.
D) The percentage of sales method encourages top management to think of growth in terms of percentages.
E) The percentage of sales method assumes the marketplace will be dynamic.