nih.gov CNAME records

CNAME Canonical name
Apex domains cannot have CNAME records.

Question and response

Question

dig nih.gov. NS

Answer

nih.gov. 1 NS ns2.nih.gov. nih.gov. 1 NS ns.nih.gov. nih.gov. 1 NS ns3.nih.gov.

Authority

The response has no authority records.

Additional

ns.nih.gov. 1 A 128.231.128.251 ns2.nih.gov. 1 A 128.231.64.1 ns3.nih.gov. 1 A 165.112.4.230 . 0 OPT ; payload 1232, xrcode 0, version 0, flags 0