多项选择题
A. Flex Links
B. loop free U
C. looped square
D. looped triangle
E. loop-tree inverted U
单项选择题 WhichofthefollowingistrueconcerningbestdesignpracticesattheswitchedAccesslayerofthetraditionallayer2EnterpriseCampusNetwork？（）
单项选择题 WhichoftheserecommendationsismostappropriateforthecorelayerintheCiscoCampus Architecture？（）
单项选择题 Thereare3stepstoconfirmwhetherarangeofIPaddresscanbesummarized.Whenofthefollowingisusedineachofthese3steps？（）