Apex domains cannot have CNAME records.
Question and response
Question
dig megapath.net. NS
Answer
megapath.net. 4 NS ns3.megapath.com.
megapath.net. 4 NS ns1.megapath.com.
megapath.net. 4 NS ns2.megapath.com.
Authority
The response has no authority records.
Additional
ns1.megapath.com. 4 A 216.132.229.53
ns2.megapath.com. 4 A 216.132.230.53
ns3.megapath.com. 4 A 216.132.231.53
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0