Which device creates separate collision domains while maintaining a single broadcast domain?

The choice of a switch is accurate because a switch operates at the data link layer (Layer 2) of the OSI model and is specifically designed to create separate collision domains for each connected device. This means that when devices are connected to a switch, they can transmit data simultaneously without causing collisions, as each port on a switch has its own collision domain.

However, switches maintain a single broadcast domain when operating in a typical configuration, enabling all devices within that broadcast domain to receive broadcast packets. When a device sends out a broadcast frame, the switch forwards that frame to all other devices in the same broadcast domain, allowing for effective communication.

This behavior contrasts with routers, which separate both broadcast and collision domains by routing traffic between different IP networks. Hubs do not create separate collision domains; rather, they operate as a single collision domain, where all connected devices share the same bandwidth and collisions can occur. Firewalls, while integral to network security, do not function specifically in terms of creating collision or broadcast domains in the same way switches and routers do.

Thus, the role of a switch in allowing multiple devices to communicate simultaneously without collisions while still broadcasting to all devices within a specific segment of the network is why it is the correct answer.