问题
单项选择题
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 al 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．Coaxial cable
B．Optical fiber
C．Unshielded Twisted-pair Cable
D．Shielded Twisted-pair Cable
答案
参考答案：B
解析：Optical fiber译为光纤。Coaxial cable为同轴电缆。Unshielded Twisted-pair Cable为非屏蔽双绞线。Shielded Twisted-pair Cable为屏蔽双绞线。答案为B。