Apex domains cannot have CNAME records.
Question and response
Question
dig fr. NS
Answer
fr. 5 NS d.nic.fr.
fr. 5 NS g.ext.nic.fr.
fr. 5 NS f.ext.nic.fr.
Authority
The response has no authority records.
Additional
d.nic.fr. 8465 A 194.0.9.1
f.ext.nic.fr. 60771 A 194.146.106.46
g.ext.nic.fr. 22797 A 194.0.36.1
d.nic.fr. 8465 AAAA 2001:678:c:0:0:0:0:1
f.ext.nic.fr. 60771 AAAA 2001:67c:1010:11:0:0:0:53
g.ext.nic.fr. 22797 AAAA 2001:678:4c:0:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0