It is known that the climate on earth has fluctuate in the past, but the present concern is that there will be a significant climate change because of the___

a. population of people on Earth

b. addition of carbon dioxide to the atmosphere

c. addition of oxygen to the atmosphere

d. deterioration of the atmosphere

Option B. Because of the addition of carbon dioxide to the atmosphere. Either by burning large quantities of fossil fuels, the release of gases by exhaust pipes or other human activities, over the last 100 years, humans have added large amounts of greenhouse gases particularly CO2 more than would be released through natural processes such as decay or respiration. Much more CO2 is now released into the atmosphere than can be reabsorbed by plants and the oceans. This climate change also paves way for global warming which is essentially the depletion of the earth's ozone layer because the planet's atmosphere contains greenhouse gases.