In Promotion to Business Customers, Personal Selling Is Often the Dominant

In promotion to business customers, personal selling is often the dominant promotion method because:

A) there are fewer business customers than final consumers.
B) the sales message may need to be adjusted to the needs of different people in the firm.
C) purchases are typically large and thus justify the effort.
D) buyers are more likely to have technical questions.
E) all of the above.