Apex domains cannot have CNAME records.
Question and response
Question
dig ohioboardofnursing.org. NS
Answer
ohioboardofnursing.org. 5 NS ns1.ohioboardofnursing.org.
ohioboardofnursing.org. 5 NS ns2.ohioboardofnursing.org.
Authority
The response has no authority records.
Additional
ns1.ohioboardofnursing.org. 5 A 95.214.52.152
ns2.ohioboardofnursing.org. 5 A 91.223.3.253
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0