A、Routing should occur at the access layer ifvoice VLANs are utilized. Otherwise， routing should occur at the distribution layer.

B、Routing should always be performed at the distribution layer.

C、VLANs should be localized to a switch.

D、VLANs should be localized to a single switch unlessvoice VLANs are being utilized.

E、Routing should not be performed between VLANs located on separate switches.