Apex domains cannot have CNAME records.
Question and response
Question
dig fancs.com. NS
Answer
fancs.com. 5 NS edns116.ultradns.net.
fancs.com. 5 NS edns116.ultradns.org.
fancs.com. 5 NS edns116.ultradns.biz.
fancs.com. 5 NS edns116.ultradns.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0