This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
Mature defence mechanism is seen in: 
Select and explain. 
A. Altruism, B. Repression, C. Regression, D. None
A: Altruism
Answer: A: Altruism 
Explanation: A i.e. Altruism