Apex domains cannot have CNAME records.
Question and response
Question
dig elasticbeanstalk.com. NS
Answer
elasticbeanstalk.com. 5 NS ns-846.awsdns-41.net.
elasticbeanstalk.com. 5 NS ns-1235.awsdns-26.org.
elasticbeanstalk.com. 5 NS ns-1537.awsdns-00.co.uk.
elasticbeanstalk.com. 5 NS ns-416.awsdns-52.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0