A customer reports they can no longer access their services and a network administrator has been assigned to investigate. A UFD disabled error status appears on all ports. What caused the issue?

A. Spanning tree Loop-guard was implemented on the uplink-state group.

B. One of the upstream interfaces is an uplink-state group went down.
C. There was no issue; this is normal behavior.
D. Both a port channel and its members were assigned to an uplink-state group.