Apex domains cannot have CNAME records.
Question and response
Question
dig cloud4c.com. NS
Answer
cloud4c.com. 5 NS ns5.ctrls.in.
cloud4c.com. 5 NS ns20.ctrls.in.
Authority
The response has no authority records.
Additional
ns20.ctrls.in. 2 A 45.249.109.172
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0