Answer: Option D.
A decrease in the amount of carbondioxide
Explanation:
Photosynthesis is the process whereby green plants use light energy from sun with carbon dioxide and water to produce glucose and oxygen.
For photosynthesis to take place, sunlight must be available, carbondioxide, water and temperature must be available. Carbon dioxide is needed for photosynthesis to produce glucose.
A decrease in carbon dioxide in the atmosphere will reduce the rate of photosynthesis.
6CO2+6H2O in the presence of sunlight-C6H12O6+6O2.
