Answer: D. Both populations developed techniques that allowed them to alter their environments to suit their needs.
In the 15th century, the populations of Europe and America were not in contact. In fact, for most of the century, they were not even aware of each other's existence.
Nevertheless, despite such separate development paths, there were some commonalities between all cultures. For example, the fact that they had all learned to use their environment to their advantage.
An example of that in North America is the case of the people of Central Mexico. They were able to learn how to farm on water, as their city was in the middle of a lake with very little land. In the case of Europe, developments such as the water mills used the natural resources people had to their advantage, and as a consequence altered their natural environment.
