Which three factors make optical a critical component of service provider networking?
(Choose three.)

A.
Optical networking is the foundation of all WANs.

B.
Many models of optical hardware have reached end-of-life.

C.
Optical hardware churns frequently and needs frequent replacement.

D.
Packet networking and optical hardware are converging.

E.
Optical local area networks are gaining in popularity.

F.
Optical hardware has a long 10-15 year life span.