We pick b.root-servers.net, one of the 13 root servers (1), and ask it about c.ci-servers.org and learn that org is delegated to six name servers (2), so we ask b0.org.afilias-nst.org where we learn that ci-servers.org is delegated to three name servers, including ns2.rapidswitch.com (3), so we ask that one and get the following answer: