正解:B
In the context of HSRP (Hot Standby Router Protocol), to ensure that a secondary switch takes over immediately as the active router if the interlink with the primary switch fails, preempt must be enabled, and tracking must be configured for the interface connecting to the primary switch. The correct command set would configure HSRP for VLAN 1000 on SW2 with a lower priority than the primary (to make it secondary) and track an interface or object that represents the interlink. If that tracked object goes down, it will decrement the priority of SW2, potentially making it higher than SW1 and causing an immediate failover to SW2.