Which statement is correct about this situation?

An administrator is replacing the current access switches with AOS-CX switches. The access layer switches must authenticate user and networking devices connecting to them. Some devices support no form of authentication, and some support 802.1X. Some ports have a VoIP phone and a PC connected to the same port, where the PC is connected to the data port of the phone and the phone’s LAN port is connected to the switch.

Which statement is correct about this situation?
A . 802.1X must be configured to work in fallback mode
B . Device fingerprinting is required for authentication
C . The client-limit setting for port access needs to be changed
D . Device mode should be implemented

Answer: C