The trade barrier being used corresponds to option D: Tariff. Also, the use of an embargo can be effective in putting a complete stop to trades with another country.
Trade barriers are an effective means of stopping or lowering trades with another entity. In the question given, Country B has added an extra fee to oil being imported from Country A. This trade barrier corresponds to the definition of a Tariff.
On the other hand, when the trade barrier in question corresponds to an embargo, it represents an effective means by which a country can put an end to trades with other countries. An Embargo is when a product or good is confiscated for not complying with rules and regulations, for example, a product imported from a country that is not allowed.
Finally, in order for Amy to accurately determine the price of her products in foreign countries, the most ideal solution would be to form a treaty with those countries that sets the pricing for similar products. However, the existence of a system for exchanging currency can also be an effective way to make sure prices are at a reasonable level for the local economy.
To learn more visit:
https://brainly.com/question/8000501?referrer=searchResults