Which IPv6 address is appropriate for anycast-assigned distributed services?

The correct answer is 2001:db8:0234:ca3e::1/128 because anycast addresses are globally routable unicast addresses that are assigned to multiple interfaces, with packets sent to the nearest interface. A /128 prefix length indicates a single host address, which is suitable for an anycast assignment where the same address is used by multiple devices. FF00:1/12 is a multicast address range. FE80::1/10 is a link-local address, which is not globally routable. 2002:db84:3f30:ca84:be76:2/64 is a global unicast address with a /64 prefix, typically used for a network segment, not a specific anycast host.