Which two reasons to deploy UDLD on a switch are true? (Choose two.)
A . It can interact with Layer 1 mechanisms to monitor the status of physical links.
B . It can replace Cisco Discovery Protocol.
C . It can replace spanning tree.
D . It can prevent forwarding loops that result unidirectional links.
E . It can interact with Layer 2 mechanisms to monitor the status of physical links.
Answer: AD