Refer to the exhibit.
A pair of LTM devices are deployed in a high-availability (HA) pair as the diagram shows. After inserting a
new rule on the firewalls, the LTM devices become Standby. The rule drops all outbound sessions to the
Internet. Only inbound connections are allowed from the Internet.
There are no other changes to the environment.
What triggered the LTM device failover?

A.
HA Group

B.
Auto Failback

C.
VLAN Failsafe

D.
Gateway Failsafe