Which of the following technologies allows multiple logical subnets to span an entire physical switched network？（）

A. HBA
B. PBX
C. VoIP
D. NIC

A.Son
B.Father
C.Grandfather
D.Great-grandfather

A. Server virtualization increases server application performance allowing productivity to be increased.
B. Server virtualization simplifies server administration and reduces the IT department staffing needs.
C. Server virtualization implements higher security measures at the server OS level reducing the need for other security implementations.
D. Server virtualization is a more efficient use of hardware for multiple servers reducing the resource utilization.