Peter, a security engineer, is trying to inventory all servers in a rack. The engineer launches RDP sessions to five different PCs and notices that the hardware properties are similar. Additionally, the MAC addresses of all five servers appear on the same switch port. Which of the following is MOST likely the cause?
A. The system is running 802.1x.
B. The system is using NAC.
C. The system is in active-standby mode.
D. The system is virtualized.