Note: If you drag the bounding box handles instead of the centerpoint, you change the size of the nested element.
You can also select nested elements using the Select commands. These commands make it very easy to select pasted-in elements and graphics.
Use the regular Selection tool to select the object. This selects the main container that holds the nested elements.

The first click with the Selection tool selects the frame that holds the nested image.
Choose Object > Select > Content. This selects the item that was pasted into the main container. In the case of a nested element, this is the frame that holds the placed graphic.

The Select > Content command selects the frame that was pasted into the main container.
Tip: Use the Selection tool to move this object by dragging its centerpoint.
You can choose Object > Select > Content again to select the placed graphic.

Choose Select>Content again to select the graphic inside the frame.
If you have selected objects within the nested elements, you can choose Object > Select > Container to select upwards through the nested elements.