Answer:
Continuity theory
Step-by-step explanation:
For Continuity Theory, the last stage of life (old age in this case) is a prolongation of the preceding periods, although there is a recognition of the discontinuity of social situations. According to this theory, the different states of the life cycle are characterized by a high degree of continuity, with the adaptation of individuals to old age influenced by their previous personality and lifestyle. It is this theory that explains the behaviors that the couple, exposed in the question, are having in old age.