A Clone object is a copy that is linked to the original (parent) so that if you modify the original, the Clone will also change.
To make a Clone:
Unlink clone ( Alt + Shift + D or Edit > Clone > Unlink clone ) separates a clone definitively from its parent, effectively making it only a copy.
When you can delete the original, the links between the clones and the original object are automatically broken.
Use Select original ( Shift + D or Edit > Clone > Select original ) to find the parent of a selected clone