正解:C
Explanation
In an active/active high availability (HA) firewall pair, the firewall that is currently processing traffic is in the
"Active" state. This state indicates that the firewall is fully functional and can own sessions and set up sessions. An active firewall can be either active-primary or active-secondary, depending on the Device ID and the HA configuration. An active-primary firewall connects to User-ID agents, runs DHCP server and DHCP relay, and matches NAT and PBF rules with the Device ID of the active-primary firewall. An active-secondary firewall connects to User-ID agents, runs DHCP server, and matches NAT and PBF rules with the Device ID of the active-secondary firewall. An active-secondary firewall does not support DHCP relay1. References: HA Firewall States, PCNSE Study Guide (page 53)