Close Buyer-Seller Relationships May Not Make Sense Because

Close buyer-seller relationships may not make sense because

A) flexibility may be reduced for the firms involved.
B) not all purchases are important enough to the buyer to justify a close relationship with a supplier.
C) some suppliers do not want to deal with buyers who place small orders.
D) there are situations in which the buyer could get reduced prices by letting suppliers compete for the buyer's business.
E) All these answers are correct.