根多分枝，微弯曲，“过桥”较长（）

A.味连

B.雅连

C.云连

D.白芍

E.赤芍

In (66) the strength of the carder 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．NAT

B．NCP

C．DDN

D．DNS