Asystem for registering genealogical trees allows different users to check if they have coincident people in their own trees. If this is the case, the shared person is marked in each tree as equivalent to the other. Thus two cousins, for example, who have the same grandfather, may have a coincident registry in their trees. Which of the three strategies of object joining is best for dealing with this case?

Why? Elaborate a model for representing people in the genealogical trees using that pattern.