单项选择题
Which benefit does digital subscriber line (DSL) systems for broadband access provide to the user?（）
A.Dedicated lines for high security data transfer
B.Data and audio signals that share the same communications infrastructure
C.Secure access to company extranet
D.Simple solution for high-quality digital video using coaxial cable
多项选择题 Which three are benefits of A virtualized data center solution over A typical implementation?（）
单项选择题 What is a benefit of Internet protocol (IP) telephony?（）
单项选择题 Controlling costs that are associated with network issues, keeping unexpected problems from affecting productivity, and achieving business goals are characteristics of which cisco offering?（）