单项选择题
A. Hosts use a logical ring topology.
B. Hosts use a logical bus topology
C. Hosts must wait for an electronic signal to transfer data.
D. Hosts are directly connected to a wiring concentrator called a MSAU.
多项选择题 Two stations on a LAN transmit at the same time, resulting in a collision. What happens when a collision occurs on the network?（）
单项选择题 Which of the addresses below is an example of a valid unicast address?（）
单项选择题 Which one of the protocols below allows a router to respond to an ARP request destined to a remote host?（）