We pick d.root-servers.net, one of the 13 root servers (1), and ask it about 3.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.2.1.0.7.7.c.3.1.1.0.0.2.ip6.arpa and learn that ip6.arpa is delegated to six name servers (2), so we ask b.ip6-servers.arpa where we learn that 3.1.1.0.0.2.ip6.arpa is delegated to eight name servers, including sec3.apnic.net (3), so we ask that one and get the following answer:
Authoritative answer
ANSWER for 3.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.2.1.0.7.7.c.3.1.1.0.0.2.ip6.arpa.