Which statement about object group is true?

Which statement about object group is true?

A.
Object groups can contain other object groups.

B.
You cannot drag a program unit to an object group.

C.
Object groups contain copies of the original objects.

D.
You can delete the original objects without affecting the object group.

E.
You can delete the object group without affecting the original objects.

F.
Dragging a block to an object group does not place its triggers in the object group.