The correct answer is D. global warming.
Carbon sequestration is the process of capturing and storing carbon dioxide, either from the atmosphere or from industrial processes. It is a strategy used to control global warming by reducing the amount of carbon dioxide in the atmosphere.
Pollution is the contamination of the physical and biological components of the Earth/atmosphere system to such an extent that normal environmental processes are adversely affected. It can take the form of chemical substances or energy, such as noise, heat or light.
Population explosion is a rapid increase in the number of people in a population. It is caused by a number of factors, including high birth rates, low death rates, and immigration.
Desertification is the process of land degradation in arid and semi-arid areas. It is caused by a number of factors, including climate change, human activities, and natural disasters.
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