Apex domains cannot have CNAME records.
Question and response
Question
dig secure.jp. NS
Answer
secure.jp. 3 NS ns2.cpi.ad.jp.
secure.jp. 3 NS ns3.cpi.ad.jp.
Authority
The response has no authority records.
Additional
ns2.cpi.ad.jp. 3 A 122.200.253.231
ns3.cpi.ad.jp. 3 A 122.200.212.131
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0