You are an administrator of an active/passive cluster of MAG Series devices running in mixed- mode configuration (IF-MAP server and authenticating users). The active user count is quickly approaching the maximum limit of the cluster. You have been directed to reconfigure the cluster to an active/active cluster and add a new license to increase the total number of active users the cluster can support. What must you do before changing the cluster configuration?（）

• A、Apply the new license to the passive node of the cluster.
• B、Configure an external load balancer to hold the V IP.
• C、Disable the active node in the cluster.
• D、Remove the IF-MAP server configuration.