Apex domains cannot have CNAME records.
Question and response
Question
dig novartis.com. NS
Answer
novartis.com. 5 NS a7-64.akam.net.
novartis.com. 5 NS a1-254.akam.net.
novartis.com. 5 NS dns1.novartis.com.
novartis.com. 5 NS a28-67.akam.net.
novartis.com. 5 NS dns2.novartis.com.
novartis.com. 5 NS dns3.novartis.com.
novartis.com. 5 NS dns4.novartis.com.
novartis.com. 5 NS a2-66.akam.net.
novartis.com. 5 NS a9-65.akam.net.
novartis.com. 5 NS a24-65.akam.net.
Authority
The response has no authority records.
Additional
dns1.novartis.com. 5 A 160.62.4.7
dns2.novartis.com. 5 A 160.62.7.59
dns3.novartis.com. 5 A 160.62.14.115
dns4.novartis.com. 5 A 160.62.14.116
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0