WhichthreefunctionsareassociatedwithaCiscoUnifiedCallManager？（）

A.connectstraditionaltelephonydevicestovoiceoverIPinfrastructure
B.convertsanalogsignalstodigitalformat
C.performsvoicecompression
D.performscallprocessing
E.performsdialplanadministration
F.performssignalinganddevicecontrol

【参考答案】

D, E, F