Apex domains cannot have CNAME records.
Question and response
Question
dig alumni.uct.ac.za. NS
Answer
alumni.uct.ac.za. 2 NS dns1.uct.ac.za.
alumni.uct.ac.za. 2 NS dns2.uct.ac.za.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0