What happens if all CTI ports for the configured CTI Port Group are busy when a new call arrives?（）

• A、Caller will receive network busy treatment.  
• B、Caller will receive ringing treatment.  
• C、CallManager will forward the call to the directory number configured for forward-on busy for this CTI Route Point in CallManager.  
• D、An exception is raised, but the call is accepted and processed.  
• E、CallManager will forward the caller to the directory number configured in IPCC Express for overflow