Apex domains cannot have CNAME records.
Question and response
Question
dig wad.pl. NS
Answer
wad.pl. 5 NS ns1.wad.pl.
wad.pl. 5 NS ns2.wad.pl.
Authority
The response has no authority records.
Additional
ns1.wad.pl. 5 A 89.22.208.2
ns2.wad.pl. 5 A 89.22.208.10
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0