By default, which character indicates the UNIX shell prompt?（）

A. The packets have exceeded the time-to-live value
B. There is a loop
C. The asterisks indicate a response time out
D. The asterisks indicate that the traceroute is completed.

A. If a switch is used, the collision domain is limited to each device and the switch
B. If a hub is used, the collision domain is limited to each device and the hub
C. If a hub is used, the collision domain includes all devices connected to the hub
D. If a switch is used, the collision domain includes all devices connected to the switch

A. Broadcast domains require that the participating devices connect to common switches or hubs
B. Broadcast domains consist of devices reachable by frames addressed to the Layer 2 broadcast address
C. Broadcast domains require a gateway device such as a router
D. Broadcast domains consist of devices that reside on the same VLAN