Which of the following best describes the role of an ARP cache?

The role of an ARP cache is primarily to map IP addresses to MAC addresses. This function is critical in networking, as it enables devices to communicate over a local area network (LAN). When a device wants to send data to another device using its IP address, it needs to know the corresponding MAC address to deliver the data at the data link layer. The ARP (Address Resolution Protocol) cache temporarily stores these mappings so that the device does not need to repeatedly resolve the IP address for MAC address conversion, which enhances communication efficiency and reduces network traffic.

The presence of an ARP cache significantly improves the speed at which devices can communicate, as the cache provides quick access to the required MAC address without needing to send out ARP requests each time. This caching mechanism reduces the overall workload on the network.

Other options do not accurately describe the ARP cache's function. For example, the cache does not store IP addresses permanently or manage routing table entries, which are functions performed by routers. Additionally, while the cache may indirectly support efficient network traffic handling, it does not track network traffic itself.