Foreign policy that is aimed aimed at controlling foreign trade by holding colonies and defending them against other foreign powers is: imperialism
Imperialism refers to the view that a country should dominate others in a certain way in order increase its power. Controlling foreign trades by holding colonies is a form of political and economical domination that was popular among Empires in Europe.
The correct answer between all the choices given is the second choice or letter B. I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.