This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anesthesia, Subject name: Pharmacology
[{'content': 'The primary mechanism of action of local anesthetics is \nSelect and explain. \nA. Blockade of voltage-gated sodium channels, B. Stimulation of voltage-gated N-type calcium channels, C. Activation of ligand-gated potassium channels, D. Blockade the GABA-gated chloride channels', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The primary mechanism of action of local anaesthetics is the blockade of voltage-gated sodium channels <img class="fr-fic fr-dib" style="width: 300px;" src=" /> Ref: Katzung 13e pg:443', 'role': 'assistant'}]