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: Pharmacology
[{'content': 'Which of the following property of the drug will enable it to be used in low concentration ? \nSelect and explain. \nA. High affinity, B. High specificity, C. Low specificity, D. High stability', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]