Apex domains cannot have CNAME records.
Question and response
Question
dig dns.it. NS
Answer
dns.it. 5 NS a.dns.it.
dns.it. 5 NS v.dns.it.
dns.it. 5 NS dns.nic.it.
dns.it. 5 NS m.dns.it.
dns.it. 5 NS r.dns.it.
dns.it. 5 NS nameserver.cnr.it.
Authority
The response has no authority records.
Additional
a.dns.it. 47121 A 194.0.16.215
m.dns.it. 94257 A 217.29.76.4
r.dns.it. 37604 A 193.206.141.46
v.dns.it. 35400 A 194.0.25.44
dns.nic.it. 50388 A 192.12.192.5
nameserver.cnr.it. 171602 A 194.119.192.34
a.dns.it. 47121 AAAA 2001:678:12:0:194:0:16:215
m.dns.it. 94257 AAAA 2001:1ac0:0:200:0:a5d1:6004:2
r.dns.it. 37604 AAAA 2001:760:ffff:ffff:0:0:0:ca
v.dns.it. 35400 AAAA 2001:678:20:0:0:0:0:44
dns.nic.it. 50388 AAAA 2a00:d40:1:1:0:0:0:5
nameserver.cnr.it. 171602 AAAA 2a00:1620:c0:220:194:119:192:34
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0