Apex domains cannot have CNAME records.
Question and response
Question
dig kiev.ua. NS
Answer
kiev.ua. 3 NS nn.ns.ua.
kiev.ua. 3 NS ho1.kv.ns.ua.
kiev.ua. 3 NS cfdf.kiev.ns.ua.
kiev.ua. 3 NS cz.ns.ua.
kiev.ua. 3 NS rcz.ns.ua.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0