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': 'ZOE is made eugenol free by \nSelect and explain. \nA. Acetic Acid, B. Alginic Acid, C. Phosphoric Acid, D. Ortho-Ethoxy Acid', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]