Atmospheric carbon dioxide levels are increasing because
A) human agriculture has greatly increased the amount of carbon dioxide given off by plants during respiration.
B) human activities have begun to release carbon that was formerly sequestered in fossil fuels into the atmosphere.
C) holes in the ozone layer have reduced the total amount of photosynthesis occurring in the biosphere.
D) the huge growth of the human population and the domestic livestock population has increased the amount of carbon dioxide being released through respiration.

Question

Quizplus · Accepted Answer

Human activities, particularly the burning of fossil fuels, have resulted in the release of large amounts of carbon dioxide into the atmosphere. This is the primary reason for the increase in atmospheric carbon dioxide levels. The other options presented are not significant contributors to this increase.

Atmospheric Carbon Dioxide Levels Are Increasing Because