How Does the Narrow Definition of Marriage as Between a Woman

How does the narrow definition of marriage as between a woman and a man create rules about gender?

A) It suggests that after the marriage, women should take on certain tasks and a certain role, and men should do the "opposite."
B) It reminds us that men and women are not equal, but are different beings who can only unite with someone of the "opposite sex" in marriage.
C) The marriage contract that presents this definition also lists tenets of male and female behavior.
D) All of the above