Increasing the light intensity increases the rate of photosynthesis, until some other factor - a limiting factor - becomes in short supply. At very high light intensities, photosynthesis is slowed and then inhibited, but these light intensities do not occur in nature.
Answer: d. All the above
Fertilizers can be deterimental to the environment. Excess use of fertilizers will result in eutrophication in the water body. Water body being more enriched with nutrients will result in excessive growth of aquatic plants. This also result in algal bloom in which algae grows on the surface of water body because of this atmospheric oxygen not able to reach the aquatic plants, hence results in oxygen depletion.
The access is most heavily limited by Climate
In an extremely dry and hot climates such as desert, it will be incredibly hard to access potable water because they evaporate really quickly
Meanwhile in a wet and cool climates such as rain forest, it will be extremely easy to access potable water