Which NDP messages allow a device to learn the network prefix for SLAAC?

The process of Stateless Address Autoconfiguration (SLAAC) allows devices to automatically configure their own IPv6 addresses by learning the network prefix from Router Advertisements (RAs). When a host connects to an IPv6 network, it sends a Router Solicitation (RS) message to request network information from local routers. The routers then respond with Router Advertisement (RA) messages, which contain crucial information about the network, including the prefix that the device will use to construct its IPv6 address.

This two-message exchange (RS/RA) is fundamental to SLAAC; the RS is used by the device to inquire about network configuration, while the RA provides the necessary network prefix and other settings such as the default gateway. Therefore, the RS/RA messages are specifically tailored for the purpose of learning the network prefix for SLAAC, making this option the correct answer.

The other choices involve different aspects of networking; for instance, NS/NA messages are part of the Neighbor Discovery Protocol as well but are used for different purposes like address resolution and confirming reachability. DHCPv6 messages like Solicit and Reply pertain to a stateful address configuration method, which is not the same as SLAAC. RS/NS does not provide the complete picture,