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多項(xiàng)選擇題

Which statements are true regarding ISDN channels?()

A. Each B channel can transmit up to 64 kbps
B. The ISDN B channel carries voice or data
C. The ISDN D channel transmits control information.
D. The D channel transmission rate varies depending on the service used.
E. HDLC or PPP can be used to encapsulate D channel information.

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