In the last few decades, the movement on the part of purchasing departments away from an adversarial approach to their suppliers to one of cooperation means that suppliers ____ . A. are more inclined to wine and dine their customers. B. need only be involved with their customers when initial deals are being made. C. must be involved at an early stage in the strategies of the companies they work with so they can anticipate needs and offer suggestions. D. don't need to be involved with the strategies of their customers. E. require little forecasing information from their customers