Concept:An official ban or restriction on trade is called an embargo.
Explanation:The sentence talks about a government action against importing used vehicles.
An
order is a general instruction, not a trade ban.
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edict is an official decree or command.
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act is a law passed by a legislature.
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embargo is a government order that bans or restricts trade with a particular country or on specific goods.
Here, the government is placing a restriction on the importation of used vehicles, which is best described as an embargo.
Answer:C. embargo