78. (p. 687) Which of the following is a reason for the significant role of salespeople in industrial markets? A. Because it is the least expensive form of communication for the selling organization. E Business buyers prefer to do business with firms they know, like, and trust, and sales personnel are the most common representative of the selling organization. C. Because advertising has been shown to not have any positive impact on awareness and sales. D. Business buyers usually are not allowed to purchase without the assistance of a sales representative. E. none of the above