With Regard to Determining How Much to Spend on Advertising,which

With regard to determining how much to spend on advertising,which of the following observations is true of the percent-of-sales approach?

A) This approach views sales as a function of advertising rather than advertising as a function of sales.
B) This approach attempts to determine the retail price by using production costs as a base.
C) The basic philosophy underlying this approach is that advertising is defensive.
D) This approach is popular in retailing.