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: Dental
[{'content': 'Highest pH of the given Root end conditioning material is of: \nSelect and explain. \nA. Citric acid., B. Doxycycline., C. EDTA., D. None.', 'role': 'user'}, {'content': 'Answer: C \nExplanation: citric acid pH=1.\nDoxycycline pH= 1.8\nEDTA pH= 7.3', 'role': 'assistant'}]