Apex domains cannot have CNAME records.
Question and response
Question
dig nic.gd. NS
Answer
nic.gd. 5 NS a.nic.gd.
nic.gd. 5 NS b.nic.gd.
nic.gd. 5 NS c.nic.gd.
nic.gd. 5 NS d.nic.gd.
Authority
The response has no authority records.
Additional
a.nic.gd. 66152 A 194.169.218.88
b.nic.gd. 66152 A 185.24.64.88
c.nic.gd. 66152 A 212.18.248.88
d.nic.gd. 66152 A 212.18.249.88
a.nic.gd. 66152 AAAA 2001:67c:13cc:0:0:0:1:88
b.nic.gd. 66152 AAAA 2a04:2b00:13cc:0:0:0:1:88
c.nic.gd. 66152 AAAA 2a04:2b00:13ee:0:0:0:0:88
d.nic.gd. 66152 AAAA 2a04:2b00:13ff:0:0:0:0:88
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0