Which two of the following are characteristics of the campus layer hierarchy tiers? (Choose
two.)

A.
The network can have two tiers of switches combined into one.

B.
Having three physical tiers is a strict requirement.

C.
A network may have four or more physical tiers of switches, if necessary.

D.
There are absolute rules for how a campus network is physically built.

E.
Each layer in the hierarchy can perform the functions of the other layers.