the transform node is the top most node. when you click on the e.g. sphere_01 in the outliner thats the transform node. looking in the attribute editor there are always sphere_01 and sphere_01_shape. in case you are not sure you could select the object and then press the up key which brings you in the hioerarchy up. the object shouldn|t be in a group cause then you might ending up in the group node. hope this was clear.