What Is One Possible Disadvantage to a Common-Law Union Compared

What is one possible disadvantage to a common-law union compared to a legal marriage?

A) Common-law spouses cannot share pensions.
B) If the relationship ends, the lower-income earner is not entitled to spousal support.
C) If the relationship ends and there are children from the relationship, the father has no custody rights.
D) Spouses cannot share health benefits.