Explanation:
Overgrazing is the major cause of desertification worldwide. Other factors that cause desertification include urbanization, climate change, overdrafting of groundwater, deforestation, natural disasters and tillage practices in agriculture that place soils more vulnerable to wind.
The correct answer is C. sewage discharge.
Even though there might even be no harmful pathogens at all if there isn't any waste, it is correct because it is implied that there is waste such as fecal matter inside of the sewage discharge.
Number of protons - 3
number of neutrons - 4
number of electrons - 3
