You deployed new fibers in your network to replace copper spans that were too long. While reconnecting the network，you experienced network problems because you reconnected wrong fibers to wrong ports. What could you do to prevent this type of problem in the future，particularly when connecting and reconnecting fiber pairs？（）
- AOnly use fiber in pairs.
- BConfigure root guard on your switches.
- CDo not use fiber but use copper.
- DConfigure UDLD to prevent one-way link conditions.