Apex domains cannot have CNAME records.
Question and response
Question
dig NET. NS
Answer
net. 3 NS e.gtld-servers.NET.
net. 3 NS g.gtld-servers.NET.
net. 3 NS m.gtld-servers.NET.
net. 3 NS c.gtld-servers.NET.
net. 3 NS j.gtld-servers.NET.
net. 3 NS k.gtld-servers.NET.
net. 3 NS d.gtld-servers.NET.
net. 3 NS b.gtld-servers.NET.
net. 3 NS h.gtld-servers.NET.
net. 3 NS f.gtld-servers.NET.
net. 3 NS i.gtld-servers.NET.
net. 3 NS a.gtld-servers.NET.
net. 3 NS l.gtld-servers.NET.
Authority
The response has no authority records.
Additional
a.gtld-servers.net. 131860 A 192.5.6.30
b.gtld-servers.net. 138209 A 192.33.14.30
c.gtld-servers.net. 132048 A 192.26.92.30
d.gtld-servers.net. 138449 A 192.31.80.30
e.gtld-servers.net. 138445 A 192.12.94.30
f.gtld-servers.net. 129040 A 192.35.51.30
g.gtld-servers.net. 128877 A 192.42.93.30
h.gtld-servers.net. 106886 A 192.54.112.30
i.gtld-servers.net. 124549 A 192.43.172.30
j.gtld-servers.net. 125164 A 192.48.79.30
k.gtld-servers.net. 128392 A 192.52.178.30
l.gtld-servers.net. 124552 A 192.41.162.30
m.gtld-servers.net. 167301 A 192.55.83.30
a.gtld-servers.net. 131860 AAAA 2001:503:a83e:0:0:0:2:30
b.gtld-servers.net. 138209 AAAA 2001:503:231d:0:0:0:2:30
c.gtld-servers.net. 132048 AAAA 2001:503:83eb:0:0:0:0:30
d.gtld-servers.net. 138449 AAAA 2001:500:856e:0:0:0:0:30
e.gtld-servers.net. 138445 AAAA 2001:502:1ca1:0:0:0:0:30
f.gtld-servers.net. 129040 AAAA 2001:503:d414:0:0:0:0:30
g.gtld-servers.net. 128877 AAAA 2001:503:eea3:0:0:0:0:30
h.gtld-servers.net. 106886 AAAA 2001:502:8cc:0:0:0:0:30
i.gtld-servers.net. 124549 AAAA 2001:503:39c1:0:0:0:0:30
j.gtld-servers.net. 125164 AAAA 2001:502:7094:0:0:0:0:30
k.gtld-servers.net. 128392 AAAA 2001:503:d2d:0:0:0:0:30
l.gtld-servers.net. 124552 AAAA 2001:500:d937:0:0:0:0:30
m.gtld-servers.net. 167301 AAAA 2001:501:b1f9:0:0:0:0:30
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0