Apex domains cannot have CNAME records.
Question and response
Question
dig f3c5.static.cnode.jp. NS
Answer
f3c5.static.cnode.jp. 5 NS b.conoha-dns.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0