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: Anaesthesia
[{'content': 'Which local anesthetic causes vasoconstriction – a) Cocaineb) Lidocainec) Bupivacained) Procaine \nSelect and explain. \nA. ac, B. bc, C. ad, D. b', 'role': 'user'}, {'content': 'Answer: A \nExplanation: All LAs are vasodilators except cocaine. Cocaine causes vasoconstriction.\n\n"Ropivacaine and bupivacaine also cause vasoconstriction". \n─ Goodman & Gilman', 'role': 'assistant'}]