A relationship between two individuals that is advantageous or necessary to both is called what?

• A. Oedipus complex
• B. Symbiosis
• C. Regression
• D. Sublimation

Answer: (B)

Symbiosis describes a close, long-term interaction between two individuals in which both benefit or where one benefits without harming the other. In human terms, this is mutualism or interdependence—a relationship that is advantageous or necessary to both parties. The other terms refer to different concepts: the Oedipus complex is about a child’s psychosexual feelings toward a parent, not mutual benefit in a relationship; regression and sublimation are defense mechanisms, describing how people cope with stress or impulses rather than describing mutual relationships. Because the question emphasizes a relationship that advantages both, symbiosis is the best fit.