Answer:
b) Permanence
Step-by-step explanation:
a) Self-disclosure is the process by which a person communicates information about oneself to another person.
b) Permanence has to do with the decision to stay next to a person.
c) Emotional devotion: means to devote and love a person
d) Fidelity: means to be loyal to the person.
Bill and Joann's commitment is to keep each other as the most important people in their lives and stay together as long as the live. This last part gives us the most important clue about it referring to Permanence since this is the decision to stay next to a person and also to make the person the most important in the other's life.