单项选择题
A. availability
B. performance
C. functionality
D. manageability
单项选择题 CiscoExpressForwarding（CEF）ismainlyusedtoincreasepacketswitchingspeed，reducingtheoverheadanddelaysintroducedbyotherroutingtechniques，increasingoverallperformance.WhichofthefollowingconcerningCEFisrecommendedbyCisco？（）
多项选择题 Whichthreestatementsaboutfirewallmodesarecorrect？（）
单项选择题 Refer to the exhibit. Which of the following is an advantage of device clustering utilizing Virtual Port Channels （vPC）？（）