Apex domains cannot have CNAME records.
Question and response
Question
dig hosts.301-moved.de. NS
Answer
hosts.301-moved.de. 5 NS dns-d.301-moved.de.
hosts.301-moved.de. 5 NS dns-f.301-moved.eu.
hosts.301-moved.de. 5 NS dns-e.301-moved.eu.
hosts.301-moved.de. 5 NS dns-a.301-moved.de.
hosts.301-moved.de. 5 NS dns-g.301-moved.de.
Authority
The response has no authority records.
Additional
dns-a.301-moved.de. 5 A 217.144.138.244
dns-d.301-moved.de. 5 A 95.211.244.25
dns-g.301-moved.de. 5 A 102.135.163.62
dns-a.301-moved.de. 5 AAAA 2a02:a00:1009:d990:8af4:0:0:53
dns-d.301-moved.de. 5 AAAA 2001:1af8:4700:a0ba:a:0:0:53
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0