Answer:
1: Burning of fossil fuel
2: Deforestation
3: Waste disposal in landfills
Explanation:
Burning of fossil fuel is the one of the primary cause of increased level of carbon dioxide in air. Deforestation refers to uncontrolled cutting down of trees which in turn increases the level of carbon dioxide in air. Plants are the natural resources that remove the carbon dioxide from air through the process of photosynthesis. Waste disposals in landfills emits methane which is one of the greenhouse gas.
