What is the function of the core tier in a traditional three tier Layer 2 network environment?

A.
The core tier connects to the Internet and with lower tier Layer 2 devices to provide Layer 3 gateway
services for the network.

B.
The core tier interfaces with lower tier devices and provides a high-speed interconnect with the north-bound
WAN edge device.

C.
The core tier provides network connectivity to end-user devices and other hosts and enforces network
access policy.

D.
The core tier relays traffic between the lower tier Layer 2 devices and functions as the gateway to the upper
tier device.