Apex domains cannot have CNAME records.
Question and response
Question
dig AFRINIC.NET. NS
Answer
afrinic.net. 2 NS ns3.afrinic.net.
afrinic.net. 2 NS afrinic.authdns.ripe.net.
afrinic.net. 2 NS ns1.afrinic.net.
afrinic.net. 2 NS ns2.afrinic.net.
afrinic.net. 2 NS rirns.arin.net.
afrinic.net. 2 NS ns4.apnic.net.
Authority
The response has no authority records.
Additional
ns1.afrinic.net. 2 A 196.216.2.1
ns2.afrinic.net. 2 A 196.216.168.10
ns3.afrinic.net. 2 A 204.61.216.100
ns1.afrinic.net. 2 AAAA 2001:42d0:0:0:0:200:2:1
ns2.afrinic.net. 2 AAAA 2001:43f8:120:0:0:0:0:10
ns3.afrinic.net. 2 AAAA 2001:500:14:6100:ad:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0