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': 'Record base thickness over crest & facial slope of ridge should be? \nSelect and explain. \nA. 1 mm, B. 2 mm, C. 3 mm, D. 4 mm', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Record base thickness:\nCrest & facial slope of ridge = 1 mm (Less thickness helps to provide additional space for teeth placement)\nHard palate & Lingual flange in mandibular denture base = 2 mm (Provide strength & rigidity)', 'role': 'assistant'}]