What design will effect traffic flows in the Data Center Core layer?

A.
The domain needed to extend a VLAN from one switch to another is determined at the core layer

B.
With a 3 layer (Access, Aggregation, Core) design the Layer 2 domain must be configured across
the Core for VLAN extension to occur

C.
Extending Layer 2 through a core causes path blocking by STP and has the risk of uncontrollable
broadcast issues related to extending Layer 2 domains, and therefore should be avoided

D.
Server-to-server traffic typically travels between aggregation modules by way of the core, while
backup and replication traffic remains within the aggregation module