Which of the Following Is True About Indirect Marketing Channels

Which of the following is true about indirect marketing channels?

A) In such channels, marketing must be targeted to shoppers who research products online and then purchase them at retail stores.
B) They refer to online stores that manufacture their own products and sell them to consumers worldwide via their own website.
C) In such channels, the producer must perform all marketing functions.
D) In such channels, intermediaries are inserted between the producer and consumers and perform numerous channel functions.