Which of the following statements is correct regarding an integrated omni$-$channel marketing strategy?

A$.$ In omni$-$channel marketing, each channel should be managed by a separate manager who is responsible for that channel's profits.

B$.$ As an incentive for channels to cooperate or coordinate, the best solution is to compensate channel managers based on total profits across channels.

C$.$ The marketing mix variables must always be identical across channels.

D$.$ If a channel is not highly profitable, it should be discontinued.

E$.$ Catalogs can play a critical role in cutting through the clutter of online marketing and creating a direct line of communication with consumers.