Mark Believes He Has Found a Sure-Fire Way to Save

Mark believes he has found a sure-fire way to save money.He advises his friends,"Buy directly from the manufacturer.Any time intermediaries get involved,you'll pay a higher price.After all,every intermediary involved in the marketing process must charge enough to earn a profit." Mark's advice:

A) is never true.Markets that make use of intermediaries can always provide goods at lower cost than those that rely on direct distribution.
B) is not valid in many cases.Intermediaries do add costs to products,but they also create values by performing marketing functions efficiently.In many cases the values they create more than offset the costs.
C) is impractical,because in most markets the distribution process is so complex that it is impossible to determine who the actual producer really is.
D) is entirely correct.Intermediaries must charge a high enough price for the activities they perform to earn a profit,so using intermediaries must result in a higher price.