Apex domains cannot have CNAME records.
Question and response
Question
dig t-systems.hu. NS
Answer
t-systems.hu. 5 NS ans1.t-online.hu.
t-systems.hu. 5 NS ans0.t-online.hu.
Authority
The response has no authority records.
Additional
ans0.t-online.hu. 5 A 195.228.240.85
ans1.t-online.hu. 5 A 195.56.77.76
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0