Answer: BC DISCUSSION: Local anesthetics act within the nerve membrane, where they inhibit transmission of nerve impulses by reducing sodium membrane permeability and the displacement of ionized calcium. All local anesthetics consist of a hydrophilic region and a hydrophobic region separated by an alkyl chain. The bond of the alkyl chain is either an ester or an amide, and these drugs are classified based on this bond. All local anesthetics except cocaine produce vasodilatation and are weak bases