单项选择题
Which companion switch is recommended to be installed with Cisco Smart Business Communications System？（）
A. C2950 B. C3750 C. ESW 500 D. SRW224G4
多项选择题 CiscoCatalyst4500Seriesswitchesareattractivetomedium-sizecampuseswithgrowthopportunitiesduetotheswitchesenhancedsecurityandwhichtwootherfeatures？（）
