A customer has a requirement for a server to run Windows Server 2003 Enterprise Edition and Exchange 2003 Enterprise Edition. It has been determined that 4GB RAM will be needed.  The customer is trying to decide between the two following configurations：   （1）An IBM xSeries x366 with 4 Xeon MP processors and 4 x 1GB memory DIMMs.       （2）An IBM xSeries x445 with 4 Xeon MP processors and 8 x 1GB memory DIMMs.  Which question should be asked to guide the customer in selecting the correct memory configuration？（）

• A、Is rack space an issue？
• B、Is there a high cache-hit ratio？
• C、Is this a mission-critical application？
• D、Are there plans to expand the memory to 8GB in the future？