Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-03.org. NS
Answer
awsdns-03.org. 5 NS g-ns-1030.awsdns-03.org.
awsdns-03.org. 5 NS g-ns-1603.awsdns-03.org.
awsdns-03.org. 5 NS g-ns-131.awsdns-03.org.
awsdns-03.org. 5 NS g-ns-709.awsdns-03.org.
Authority
The response has no authority records.
Additional
g-ns-131.awsdns-03.org. 5 A 205.251.192.131
g-ns-709.awsdns-03.org. 5 A 205.251.194.197
g-ns-1030.awsdns-03.org. 5 A 205.251.196.6
g-ns-1603.awsdns-03.org. 5 A 205.251.198.67
g-ns-131.awsdns-03.org. 5 AAAA 2600:9000:5300:8300:0:0:0:1
g-ns-709.awsdns-03.org. 5 AAAA 2600:9000:5302:c500:0:0:0:1
g-ns-1030.awsdns-03.org. 5 AAAA 2600:9000:5304:600:0:0:0:1
g-ns-1603.awsdns-03.org. 5 AAAA 2600:9000:5306:4300:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0