Tariffs
Im in an alternative school so take it with a grain of salt
Producers in the United States are not allowed to sell goods to a particular country because of its political policies. Tariffs are an example of what kind of trade barrier. Thus, (d) is the correct.
What is trade?
Trade is the part of economic activity that is referred to. the procedure used in trade to buy and sell goods and services. the use of money to exchange commodities and services.
There are various kinds of trade, including: the first is domestic trade, which includes wholesalers and retailers; the second is international trade, which includes import, export, and e-commerce.
The trade system is a barrier of tariff. The tariff is such kind of tax as imposed by the government as a transaction and exchange of goods to import and export. The United States as political policies do not exchange the goods to other countries because of reason are tariffs. The tariffs are fixed rate of percentage as are rises amount of the goods.
Therefore, option (d) is correct.
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