Which of the Following Is (Are)advantage(s)of Full Partnerships with Suppliers,as

Multiple Choice

Which of the following is (are) advantage(s) of full partnerships with suppliers,as compared to traditional adversarial relationships? I.They help reduce uncertainties for both buyer and supplier.
II.The full partnership is easier to establish and maintain than other relationships,so more suppliers can be dealt with.
III.The full partnership assures the lowest material price.

A) I only
B) II only
C) III only
D) I and II only
E) II and III only