单项选择题
A.5ΩB.10ΩC.15ΩD.20Ω
A.TD/T3481B.GB/T3481C.YD/T3483D.GB/T3483
A.双模光纤收发器B.共模光纤收发器C.多模光纤收发器D.其余三项都是