Answer: B. European countries exploited conquered countries for raw materials and inexpensive labor.
Step-by-step explanation:
European nations were in the habit of using the natives of the lands they conquered for inexpensive labor so that they could make more profit from production. The British for instance did this in Africa and India and the Spanish did it in the Americas.
They also exploited their colonies for raw materials which they were able to pay lower prices for and therefore use to make more profit than they would have if they had paid a fair price.