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': 'Which of the following excludes painful stimuli from awareness? \nSelect and explain. \nA. Repression, B. Reaction formation, C. Projection, D. Rationalization', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Repression is the defense mechanism which removes painful memories or unacceptable desires away from the consciousness or awareness.', 'role': 'assistant'}]