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: Medicine
[{'content': 'Which of the following statements best describes a key feature of innate immunity? \nSelect and explain. \nA. It improves with repeated exposure to a given antigen, B. It requires antigen processing for activation, C. It is not associated with primary immune deficiency, D. It includes interaction between pattern recognition receptors on phagocytes and pathogen-associated molecular patterns', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Pathogen-associated molecular patterns, found on invading pathogens, are recognised by pattern recognition receptors on phagocytic cells, allowing phagocytosis and subsequent pathogen destruction. Memory, specificity and the need for antigen processing are features of adaptive immunity. Primary immune deficiencies affecting innate immunity are well recognised.', 'role': 'assistant'}]