This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Regional anaesthesia, Subject name: Anaesthesia
[{'content': "For Bier's block drug of choice is - \nSelect and explain. \nA. Priloacaine, B. Bupivacaine, C. Lignocaine, D. None", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Lignocaine is used for Bier&;s block Bupivacaine is contraindicated in IV regional anaesthesia due to fear of arrhythmia', 'role': 'assistant'}]