What are two possible sources?

An administrator needs to populate the catalog with a vApp.
What are two possible sources? (Choose two.)

A.
An existing deployed vCloud vApp which can be published as a vApp Template.

B.
An existing deployed vSphere vApp which can be published as a vApp Template.

C.
An existing vSphere Template which can be converted to a vApp Template.

D.
An existing powered off workload which can be copied into a new vApp Template.