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': 'Palatal cusp of upper posterior teeth in complete denture patients should fall on \nSelect and explain. \nA. Crest of mandibular ridge, B. Lingual to crest of mandibular ridge, C. Buccal to crest of mandibular ridge, D. Buccal vestibule', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]