Answer:
Placement marriage among the mormón church.
Gypsy Romani marriages only among people from the same culture
Arranged marriages among people from a latin-american country and an American citizen.
Step-by-step explanation:
In the first two cases it is normally to think that for those cultural and religious movements, it is necessary to preserve the same kind of customs and beliefs and the only way to achieve this goal is to keep engaging among themselves.
In the third example, the main idea of this combination would be for Latin-Americans to be part of the North American culture and economy (First world).