Which action must be taken to assign a global unicast IPv6 address on an interface...

enable SLAAC on an interface. To derive a global unicast IPv6 address from the interface MAC address, the device must use SLAAC or an explicit EUI-64-based IPv6 configuration. SLAAC receives the IPv6 prefix from router advertisements and builds the interface identifier from the local interface value, historically using the modified EUI-64 process. Stateful DHCPv6 can assign IPv6 addresses, but that does not specifically create the address from the interface MAC address. Disabling EUI-64 would do the opposite of the requirement, and a link-local address is not the requested global unicast address. Cisco CCNA 200-301 v1.1 Network Fundamentals covers this because IPv6 address assignment is a core operational skill. The clue is ' derived from the MAC address. ' That points to SLAAC/EUI-64 behavior, not a DHCPv6 server-created address. The correct action is to enable SLAAC on the interface or use the equivalent EUI-64 address-generation method.