Which of the following is most likely to act as a base rather than a nucleophile?

Name: Which of the following is most likely to act as a base rather than a nucleophile?
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Question

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Compound III has a lone pair of electrons on the nitrogen, which makes it more likely to act as a base and accept a proton rather than participate in a nucleophilic attack. Compounds I, II, and IV have electron-withdrawing groups that make them more likely to act as nucleophiles.

Which of the Following Is Most Likely to Act as a Base