Which device operates at the Data Link Layer primarily for filtering traffic?

The correct choice focuses on bridges, which are devices that operate primarily at the Data Link Layer of the OSI model. Their main function is to filter traffic by managing the data frames that transit through them, based on MAC addresses. This filtering process helps in reducing network traffic, as a bridge can forward data only to the segments of the network that need it, preventing unnecessary data from reaching all parts of a network.

Bridges maintain a MAC address table to efficiently learn and make decisions about where to forward frames, thus enhancing the performance and management of local area networks (LANs). They help in connecting different segments of a LAN, promoting segmentation that can lead to improved overall network efficiency.

While switches also operate at the Data Link Layer and perform similar filtering functions by using MAC addresses, the question specifically asks about the device that operates at this layer primarily for filtering traffic. In this context, bridges are typically the device highlighted for being closely associated with traffic filtering, making them the most suitable choice for this particular question.