Apex domains cannot have CNAME records.
Question and response
Question
dig jeugdzorgnet.nl. NS
Answer
jeugdzorgnet.nl. 3 NS ns2.transip.eu.
jeugdzorgnet.nl. 3 NS ns1.transip.nl.
jeugdzorgnet.nl. 3 NS ns0.transip.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0