Answer:
A. Limited resources
Explanation:
One region is home to several populations of different species of living things. These species consume the natural resources of that area that are necessary for their survival. However, when a region has a very high number of populations, its natural resources are limited and even scarce, which will cause competition between the individuals of the populations.
These natural resources can be food, prey, water, habitat, among others.
With that, we can say that limited resources make the populations compete with each other.
