Which is not true of hierarchical routing?

A.
The region of a node that shares characteristics and behaviors is called an AS.

B.
Each AS uses IGP to perform routing functionality.

C.
EGP is used in the areas "between" each AS.

D.
CAs are specific nodes that are responsible for routing to nodes outside of their region.

Explanation:
Gateways are designated nodes that are responsible for routing to nodes
outside of their region. Autonomous systems (AS) are regions of nodes that share
common attributes. Interior Gateway Protocol (IGP) handles routing tasks within each
AS, while Exterior Gateway Protocol (EGP) functions "between" each AS.