Apex domains cannot have CNAME records.
Question and response
Question
dig it-ex.com. NS
Answer
it-ex.com. 5 NS ns001-frkbosohbi14o0i1.f.d-53.info.
it-ex.com. 5 NS ns001-frkbosohbi14o0i1.f.d-53.jp.
it-ex.com. 5 NS ns001-frkbosohbi14o0i1.f.d-53.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0