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': 'Which of the following cements is contraindicated in mouth breathers: \nSelect and explain. \nA. Silicate, B. ASPA, C. Polycarboxylate, D. Zinc phosphate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]