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: Surgery
[{'content': 'Success rate for intraligamentary anaesthesia \nSelect and explain. \nA. Injection under strong forward pressure, B. Injection under strong back pressure, C. Injection over supragingival tissue, D. Injection over buccal Labial fold', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]