Apex domains cannot have CNAME records.
Question and response
Question
dig bell.net. NS
Answer
bell.net. 4 NS toroondcnszs01.srvr.bell.ca.
bell.net. 4 NS mtl02vnszs07.srvr.bell.ca.
bell.net. 4 NS mtl02vnszs08.srvr.bell.ca.
bell.net. 4 NS tor63vnszp07.srvr.bell.ca.
bell.net. 4 NS tor63vnszp08.srvr.bell.ca.
bell.net. 4 NS toroon63nszp01.srvr.bell.ca.
Authority
The response has no authority records.
Additional
mtl02vnszs07.srvr.bell.ca. 4 A 207.236.176.16
mtl02vnszs08.srvr.bell.ca. 4 A 207.236.176.10
tor63vnszp07.srvr.bell.ca. 4 A 207.164.234.44
tor63vnszp08.srvr.bell.ca. 4 A 207.164.234.46
toroon63nszp01.srvr.bell.ca. 4 A 207.164.234.42
toroondcnszs01.srvr.bell.ca. 4 A 207.236.176.30
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0