Apex domains cannot have CNAME records.
Question and response
Question
dig ic.km.ua. NS
Answer
ic.km.ua. 5 NS ns.ic.km.ua.
ic.km.ua. 5 NS ns.secondary.net.ua.
Authority
The response has no authority records.
Additional
ns.ic.km.ua. 5 A 78.152.160.5
ns.ic.km.ua. 5 AAAA 2a00:6740:0:0:0:0:0:5
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0