A network administrator is seeing a posture status "unknown" for a single corporate machine on the Cisco ISE authentication report, whereas the other machines are reported as "compliant". Which option is the reason for machine being reported as "unknown"?
A. Posture agent is not installed on the machine.
B. Posture policy does not support the OS.
C. Posfure compliance condition is missing on the machine.
D. Posture service is disabled on Cisco ISE.
