Answer:
Correct answer is D. trade barriers protect a nations interests by encouraging the production of homeland goods​
Explanation:
D is the correct answer as it refers to policy known as protectionism, in which countries are protecting their interest by producing certain goods they don't want to import.
A is not correct as this doesn't ensure similar production, but quite on the contrary.
B is not correct as it can actually lead to the creation of certain barriers.
C is not correct because it doesn't have to mean that people were travel less because of this.
