To What Does the Physical Distribution Customer Service Level Refer

To what does the physical distribution customer service level refer?

A) It refers to the costs to carry a product in inventory.
B) It refers to the length of time a product is stored in inventory.
C) It refers to the effort put in by channel members to meeting customer needs.
D) It refers to the location of distribution centers.
E) It refers to the ability of a firm to deliver rapidly and dependably what customers want.