Which event triggers failover at the failover group level in an active/active failover configuration?

Which event triggers failover at the failover group level in an active/active failover configuration?

A.
The unit has a software failure

B.
Two monitored interfaces in the group fail.

C.
The no failover active command is entered in the system configuration.

D.
The no failover active group group_id command is entered in the system configuration.

E.
All interfaces in a single context fail.