What is the purpose of the restricted VLAN (authentication failed VLAN) on a Cisco Catalyst switch?

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What is the purpose of the restricted VLAN (authentication failed VLAN) on a Cisco Catalyst switch?

A. It provides configurable guest access to nonsupplicant devices that have local credentials.
B. It provides configurable guest access to devices that have a supplicant when the authenticator is down or unreachable.
C. It provides configurable guest access to nonsupplicant devices that lack local credentials.
D. It provides configurable guest access to devices that have a supplicant when the authentication server is down or unreachable.
E. It provides configurable guest access to devices that have a supplicant but lack local credentials.