Which of the Following Statements Is True with Regard to Producers

 Which of the following statements is true with regard to producers?

A) Producers constitute the smallest segment of organizational buyers.
B)  Producers are characterized by their primary function being the purchase of products from manufacturers and their distribution to consumers and other organizational buyers.
C)  Producers of goods tend to be larger and more geographically concentrated than producers of services.
D)  Producers are the only class of buyers who are excluded from the purview of business-to-business marketing.