Final answer:
The correct answer is c. photosynthesis. Forest fires, respiration, and burning of fossil fuels introduce carbon gases into the atmosphere.
Step-by-step explanation:
The correct answer is c. photosynthesis. Photosynthesis is actually a process by which carbon dioxide is taken in from the atmosphere and converted into oxygen. In this process, plants use sunlight, chlorophyll, and water to convert carbon dioxide into glucose and release oxygen as a byproduct. Forest fires, respiration, and burning of fossil fuels are all ways in which carbon gases are introduced into the atmosphere.
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