When active/active failover is implemented on the Cisco ASA, how many failover groups are supported on the Cisco ASA?

A.
1

B.
2

C.
1 failover group per configured security context

D.
2 failover groups per configured security context

Explanation:
http://www.cisco.com/en/US/products/ps6120/products_configuration_example09186a00808340 58.shtml#act1
Active/Active Failover Overview
Active/Active failover is only available to security appliances in multiple context mode. In an Active/Active failover configuration, both security appliances can pass
network traffic. In Active/Active failover, you divide the security contexts on the security appliance into failover groups. A failover group is simply a logical group of
one or more security contexts. You can create a maximum of two failover groups on the security appliance. The admin context is always a member of failover group
1. Any unassigned security contexts are also members of failover group 1 by default. The failover group forms the base unit for failover in Active/Active failover.
Interface failure monitoring, failover, and active/standby status are all attributes of a failover group rather than the unit. When an active failover group fails, it
changes to the standby state while the standby failover group becomes active. The interfaces in the failover group that becomes active assume the MAC and IP
addresses of the interfaces in the failover group that failed. The interfaces in the failover group that is now in the standby state take over the standby MAC and IP
addresses.
Note: A failover group failing on a unit does not mean that the unit has failed. The unit may still have another failover group passing traffic on it.