People gain insight into the unconscious origins of their disorder is a central aim of

Psychoanalysis

Explanation:

Psychoanalysis is a phenomenon that was proposed by Sigmund Freud. Many psychologists think that people can be cured by making them conscious of unconscious thought. It is also called catharsis. It is the phenomena through which a person can be healed through this process. It is a process through that repressed emotions can be healed.  

Thus psychoanalysis is the old psychotherapist technique to resolve the problems.  

the answer is b, encourage free trade