What is one way that humans disrupt Earth's gaseous biogeochemical cycles? 

A)  by using mist systems to water crops 
B)  by mining limestone 
C)  by adding carbon dioxide to the atmosphere as a result of combustion 
D)  by emitting waste heat from air conditioners

Gaseous Biogeochemical Cycles

The circulation of chemical elements like carbon and nitrogen through the atmosphere, involving exchanges between living organisms and physical processes.

Carbon Dioxide

A gas devoid of color and smell, produced from the burning of carbon-containing compounds and the act of breathing. Naturally found in the environment, it is essential for plant photosynthesis.

Atmosphere

The layer of gases surrounding the Earth that is held in place by gravity and is composed of nitrogen, oxygen, and trace gases.