Answer: British authorities based their colonial commercial policies on the theory of MERCANTILISM.
Explanation: Mercantilism is the system whereby a country amass wealth for itself at the expense of another country. The prosperity of a nation depends upon its supply of capital, and that the global volume of trade is unchangeable. This is done by increasing export significantly and reducing imports. It was used by the British to significantly amass wealth by importing commodities to Africa in exchange for gold and other precious metals.