Why did europeans use one-crop economies in their colonies?

In the time of the colonial era, European countries followed mercantilism.  This helped the production of agricultural products which could be exported to their motherland as raw materials for industries production there.  It also increased the importance of the capital market in the life of the colonial peoples.  As a result, larger numbers of land was shifted from growing food crops to growing “cash crops,”.

john smith was the first englishman to sail around the world. francis bacon served as attorney general and lord chancellor of england. he took up aristotelian ideas, arguing for an empirical, inductive approach, known as the scientific method, which is the foundation of modern scientific inquiry.

i believe the answer is d.