问题详情

In(66)the strength of the carrier signal is varied to represent binary 1 or 0.(67)is a system that can map a name to an address and conversely an address to an name.(68)is a three -way handshaking authentication protocol that it"s packets are encapsulated in the point - to -point protocol.(69)is an approach that enables an ATM Switch to behave like a LAN switch.(70)is an guided media which is made of glass or plastic and transmits signals in the form. of light.
A．FDM
B．DSK
C．FCK
D．ASK请帮忙给出正确答案和分析，谢谢！