A client roams from H-REAP AP1 to H-REAP AP2. The client is unable to associate to H-REAP AP2. H-REAP AP2 has six other clients associated to it， which continue to pass traffic. What has caused this problem？（）

• A、H-REAP AP1 lost its connection to the controller.
• B、H-REAP AP2 lost its connection to the controller.
• C、H-REAP AP1 has reached its client limit.
• D、H-REAP AP2 has reached its client limit.