What is a critical pressure in legacy data center networks?

A.
The legacy two-tier topology cannot scale out to support the large number of servers in a
modern data center.

B.
Servers need their network connectivity provisioned more quickly than is possible with manual
CLI-based processes.

C.
Legacy server hardware cannot support the virtual switches and virtual routers that virtualized
hosts require.

D.
Client-to-server traffic is increasing more quickly than server-to-server traffic, overburdening the
network core.