Anetworkisdeployedusingbestpracticesoftheenterprisecampusnetworkmodel,includinguserswithdesktopcomputersconnectedviaIPphones.GiventhatallcomponentsareQoS-capable,wherearethetwooptimallocationsfortrustboundariestobeconfiguredbythenetworkadministrator?()
A. host
B. IPphone
C. accesslayerswitch
D. distributionlayerswitch
E. corelayerswitch