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': 'Bitter taste is felt at: \nSelect and explain. \nA. Tip of the tongue., B. Lateral border of the tongue., C. Central portion of the tongue., D. Posterior portion of the tongue.', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]