A couple is evaluated at the request of their son. Hisfather isa 49-year-old man who has no past psychiatric history, and his mother is a 50-year-old woman who has a history of schizophrenia with prominent paranoid delusions. Last year they moved from the city to a farm that is relatively isolated, and they now have limited social activities outside of their marriage. Their son visited the farm to discover that his father now believes in his mother's longstanding paranoid delusions. The son shares that his mother has a dominating personality, and his father is submissive to his mother's behaviors and beliefs. Which psychoanalytic theory best explains the development of this couple's shared psychosis?

A. Structural theory

B. Attachment theory

C. Psychosexual development theory

D. Psychodynamic theory