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 type of fear is the most usually difficult to\novercome? \nSelect and explain. \nA. Long standing objective fears, B. Long standing subjective fears, C. Short term objective fears, D. Short term subjective fears', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]