Which three authentication services are supported by Cisco NAC Appliance? (Choose three.)

A.
RADIUS

B.
LDAP

C.
Kerberos

D.
TACACS+

E.
local

Explanation:
https://www.cisco.com/c/en/us/td/docs/security/nac/appliance/configuration_guide/47/cam/47cam-book/m_auth.html
Working with Existing Backend Authentication Servers
When working with existing backend authentication servers, Cisco supports the following authentication protocol types:

•Kerberos
•RADIUS (Remote Authentication Dial-In User Service)
•Windows NT (NTLM Auth Server)
•LDAP (Lightweight Directory Access Protocol)”