Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-00.com. NS
Answer
awsdns-00.com. 5 NS g-ns-1152.awsdns-00.com.
awsdns-00.com. 5 NS g-ns-1.awsdns-00.com.
awsdns-00.com. 5 NS g-ns-576.awsdns-00.com.
awsdns-00.com. 5 NS g-ns-1728.awsdns-00.com.
Authority
The response has no authority records.
Additional
g-ns-1.awsdns-00.com. 5 A 205.251.192.1
g-ns-576.awsdns-00.com. 5 A 205.251.194.64
g-ns-1152.awsdns-00.com. 5 A 205.251.196.128
g-ns-1728.awsdns-00.com. 5 A 205.251.198.192
g-ns-1.awsdns-00.com. 5 AAAA 2600:9000:5300:100:0:0:0:1
g-ns-576.awsdns-00.com. 5 AAAA 2600:9000:5302:4000:0:0:0:1
g-ns-1152.awsdns-00.com. 5 AAAA 2600:9000:5304:8000:0:0:0:1
g-ns-1728.awsdns-00.com. 5 AAAA 2600:9000:5306:c000:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0