Apex domains cannot have CNAME records.
Question and response
Question
dig telia-isp.no. NS
Answer
telia-isp.no. 5 NS m40.dh.teliadns.no.
telia-isp.no. 5 NS m41.dh.teliadns.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0