Answer:
b. institutional commitment adds value/stability to relationships
Step-by-step explanation:
In the research study, titled: "Stability of U.S. couples with children in a comparative perspective" Musick, based on the findings across Europe, it was suggested that, cohabiting parents who did not subsequently marry were much more likely to separate than married parents, while the institutional commitment adds value/stability to relationships.
In addition, it was suggested that, amongst other factors, Low education, prior childbearing, and early age at birth were associated with union instability, which is fairly consistently across countries.