Answer:
A. Mercantilism.
Step-by-step explanation:
Mercantilism is when a country tries to control the trade with another country, typically with the belief and them trying to create a market in which the receiving country can only import from the host country (as stated in the question).
It is not b, for a triangle trade implies that there are 3 countries, continent, etc. In this case, all 3 must trade with each other, and it does not fit the definition given, which gives 2 countries.
It is not c, for capitalism is defined in which a country itself has it's economy controlled by those who live in it, who can make or break the economic situation.
It is not d, for it implies that all sides of the trade agree to trade freely without imposing tariffs on each other's goods and services.
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