Apex domains cannot have CNAME records.
Question and response
Question
dig yinguoyuan.org. NS
Answer
yinguoyuan.org. 1 NS ns-43.awsdns-05.com.
yinguoyuan.org. 1 NS ns-1819.awsdns-35.co.uk.
yinguoyuan.org. 1 NS ns-712.awsdns-25.net.
yinguoyuan.org. 1 NS ns-427.awsdns-53.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0