An enterprise has two U1981s working in active/standby mode for discover recovery, and the config modify switch waittime 10 command is executed on the standby device. One morning, the active device was faulty at 09:00, and recovered at 09:05. At this time, ().
A . Services were automatically switched back to the active device immediately.
B . Services can be switched back to the active device only after a switching command is executed manually.
C . Data generated during the period when the standby node took over services was automatically
D . synchronized to the primary node after the services were switched back to the primary node.
Answer: A