Apex domains cannot have CNAME records.
Question and response
Question
dig WM.RU. NS
Answer
wm.ru. 5 NS ns.wm.ru.
wm.ru. 5 NS ns1.wm.ru.
Authority
The response has no authority records.
Additional
ns.WM.RU. 5 A 194.190.169.11
ns1.WM.RU. 5 A 178.250.159.131
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0