This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Psychoanalysis, Subject name: Psychiatry
[{'content': 'Defense mechanism in depression \nSelect and explain. \nA. Altruism, B. Projection, C. Undoing, D. Introjection', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Defence mechanism in disease Disease Defence mechanism Psychosis Projection Neurosis Repression Phobia Displacement Inhibition Depression Introjection OCD Undoing Reaction formation', 'role': 'assistant'}]