What is the implication of executing the command failover interface-policy 2 on an FWSM?

What is the implication of executing the command failover interface-policy 2 on an FWSM?

A.
The second configured failover interface policy will be applied to the FWSM

B.
The configured failover interface policy will be applied to VLAN 2

C.
The FWSM will become active when it fails to receive two consecutive heartbeats from the paired FWSM

D.
The FWSM will fail over when more than one VLAN interface fails