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': 'A patient complains of generalized soreness over the entire mandibular ridge. This is probably due to: \nSelect and explain. \nA. Occlusal imbalance, B. Excessive vertical dimension, C. Over-extended borders, D. Under-extended borders', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]