Apex domains cannot have CNAME records.
Question and response
Question
dig INfO. NS
Answer
info. 3 NS c0.info.afilias-nst.info.
info. 3 NS b2.info.afilias-nst.org.
info. 3 NS b0.info.afilias-nst.org.
info. 3 NS a0.info.afilias-nst.info.
info. 3 NS a2.info.afilias-nst.info.
info. 3 NS d0.info.afilias-nst.org.
Authority
The response has no authority records.
Additional
a0.info.afilias-nst.info. 171398 A 199.254.31.1
a2.info.afilias-nst.info. 80612 A 199.249.113.1
c0.info.afilias-nst.info. 171398 A 199.254.49.1
a0.info.afilias-nst.info. 171398 AAAA 2001:500:19:0:0:0:0:1
a2.info.afilias-nst.info. 80612 AAAA 2001:500:41:0:0:0:0:1
c0.info.afilias-nst.info. 171398 AAAA 2001:500:1b:0:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0