Refer to the exhibit.

A network engineer investigates a recent network failure and notices that one of the interfaces on the switch is still down. What is causing the line protocol on this
interface to be shown as down?

A.
There is a layer 1 physical issue.

B.
There is a speed mismatch on the interface.

C.
The interface is configured as the target of the SPAN session.

D.
The interface is configured as the source of the SPAN session.

E.
There is a duplex mismatch on the interface.

Explanation:
With the SAPN destination port, the state of the destination port is up/down by design. The interface shows the port in this state in order to make it evident that the
port is currently not usable as a production port. This is the normal operational state for SPAN destinations.

http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note09186a008015c612.
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