What role does a querier play in a network?

The role of a querier in a network is primarily associated with managing multicast group memberships, which is accurately reflected in the choice B. In the context of multicast networking, a querier is responsible for sending out IGMP (Internet Group Management Protocol) queries to determine the status of multicast group memberships among the hosts in the subnet. This allows network devices to efficiently manage and maintain the list of devices that are interested in receiving specific multicast traffic, ensuring optimal bandwidth usage and reducing unnecessary network load.

By managing these memberships, the querier plays a crucial role in the smooth operation of multicast communications, allowing for effective distribution of data to multiple recipients without flooding the network with excessive traffic. This functionality is especially important in audio and video streaming applications supported by systems like Dante, where precise and efficient data delivery is essential to maintaining audio quality.

The other roles mentioned, such as IP address assignment and segmenting collision domains, pertain to different network functionalities that do not align with the specific duties of a querier in relation to multicast group management. Understanding the distinct functions of network devices is crucial for effective network design and troubleshooting.