Which is a reason that the Ethernet protocol uses physical addresses?

A. It creates a differentiation between layer 2 and layer 3 communications.
B. It defines a logical address scheme for devices.
C. It uniquely identifies devices at layer 2.
D. It allows the node to decide if the device is remote or local.

C. MAC addresses are physical addresses that are burned into every NIC card and network device. They are unique at the Data Link layer for direct communication purposes.