Apex domains cannot have CNAME records.
Question and response
Question
dig biz.bbtec.net. NS
Answer
biz.bbtec.net. 3 NS ns002.bbtec.net.
biz.bbtec.net. 3 NS ns001.bbtec.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0