Apex domains cannot have CNAME records.
Question and response
Question
dig InFO. NS
Answer
info. 4 NS d0.info.afilias-nst.org.
info. 4 NS c0.info.afilias-nst.info.
info. 4 NS b2.info.afilias-nst.org.
info. 4 NS a0.info.afilias-nst.info.
info. 4 NS b0.info.afilias-nst.org.
info. 4 NS a2.info.afilias-nst.info.
Authority
The response has no authority records.
Additional
a0.info.afilias-nst.info. 172450 A 199.254.31.1
a2.info.afilias-nst.info. 57912 A 199.249.113.1
b0.info.afilias-nst.org. 3 A 199.254.48.1
c0.info.afilias-nst.info. 172450 A 199.254.49.1
d0.info.afilias-nst.org. 3 A 199.254.50.1
a0.info.afilias-nst.info. 172450 AAAA 2001:500:19:0:0:0:0:1
a2.info.afilias-nst.info. 57912 AAAA 2001:500:41:0:0:0:0:1
b0.info.afilias-nst.org. 3 AAAA 2001:500:1a:0:0:0:0:1
c0.info.afilias-nst.info. 172450 AAAA 2001:500:1b:0:0:0:0:1
d0.info.afilias-nst.org. 3 AAAA 2001:500:1c:0:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0