The correct answer is D) planners took water from reservoirs and used filtration systems.
City planners solved the public health problems posed by polluted rivers and lakes in that planners took water from reservoirs and used filtration systems.
City planners need to be cautious to protect the environment and not destroying it. Urbanization has been the cause of desertification and deforestation, two things that heavily affect the environment and polluted nature and water. To avoid the use of polluted water from rivers and lakes, City planners are devising systems to use water from reservoirs and through filtration systems the purify the water to make it fresh and good for drinking. This measure allows citizens to feel secure to have fresh water for human purposes.