An IPCC Express deployment requires support for 20 concurrently logged-in agents. The agents aresplit across two remote sites, and the High Availability CRS Engine, Database Server, VoIP Monitoring, and Recording server processes run at a central data center. The agents will be using CAD with 7960 phones and end-point monitoring. Very little recording and silent monitoring will be performed, and no historical reporting will be done during call center open hours. Assume the minimum number of servers is desired.  How many IPCC Express hardware servers would be required for this IPCC Express deployment?（）

• A、1 
• B、2 
• C、3 
• D、4 
• E、5