What must be enabled so an interface derives a global unicast IPv6 address from its MAC address?

SLAAC (Stateless Address Autoconfiguration) allows an IPv6 host to automatically configure its global unicast address using information from router advertisements and its own MAC address, which is then converted into a 64-bit interface identifier using the EUI-64 process. Manually assigning a link-local address is not directly related to deriving a global unicast address from a MAC address. Disabling the EUI-64 process would prevent the MAC address from being used to form the interface identifier. Deploying a stateful DHCPv6 server would provide addresses, but it's a stateful method and doesn't rely on the host's MAC address for the address generation in the same way SLAAC does.