Which type of IPv6 addresses resembles private IPv4 addresses?

Unique local addresses (ULAs) in IPv6 serve a similar purpose to private IPv4 addresses. Private IPv4 addresses, such as those defined in the ranges 10.0.0.0 to 10.255.255.255, 172.16.0.0 to 172.31.255.255, and 192.168.0.0 to 192.168.255.255, are designed for use within a local network and are not routable on the public internet.

Likewise, unique local addresses in IPv6, which fall within the range of fc00::/7, are intended for use within a local network and should not be routed in the global IPv6 internet. They allow for address uniqueness within a site or organization, making them suitable for private communications without the risk of conflicts from globally routable addresses. This close resemblance in purpose between ULAs and private IPv4 addresses is what makes unique local addresses the correct choice.

Link-local addresses (focusing on communication within a single segment) and global unicast addresses (which are routable on the public internet) do not have a private scope. Multicast addresses, used for one-to-many communication, also do not serve a