Several users from the same building are reporting connectivity issues. The SFP at that building’s IDF switch is showing a link light, but there is no link light to the corresponding switch’s SFP at the MDF. Which of the following is the MOST likely cause?
A. A crossover cable is being used.
B. DB loss is too high on all strands.
C. Only TX or RX strand is working.
D. TX and RX are reversed.