After download of the Master Installer from the Oracle Management Cloud (OMC), what is needed to install and
configure OMC agents?
A.
a registration key for your agents
B.
activating your OMC services from the My Services dashboard
C.
generating an SSH key for your Web proxy
D.
opening of port 3872 (or a port in the range 1830-1849) on your firewall
I think Answer A
https://docs.oracle.com/en/cloud/paas/management-cloud/emaig/installing-and-managing-oracle-management-cloud-agents.pdf (p2-1,9)