Answer:
D. Populations are greater in fertile areas that are close to freshwater sources, which is why more people live near rivers.
Step-by-step explanation:
Population is greatly depend on the availability of water. Those areas are densely populated areas where water is present in sufficient quantity as compared to those areas have low population density where water is in low amount. The main reason is that water plays a vital role in our daily life which is used almost in every aspects of life. We can see that deserts have less population due to less water availability and areas attached to the rivers are densely populated due to more water availability.