Apex domains cannot have CNAME records.
Question and response
Question
dig mediaworks.rs. NS
Answer
mediaworks.rs. 3 NS ns1.mediaworksit.net.
mediaworks.rs. 3 NS ns2.mediaworksit.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0