Fact 1: Carbon cycles quickly between organisms and the atmosphere.

Fact 2: An organic molecule is one involving carbon.

Given the two facts above, answer the question "What cycle quickly between organisms and the atmosphere?" with the following options: 
- chlorofluorocarbons
 - organic molecules
 - Most plants
 - Greenhouse gasses
 - Greenhouse gases
 - emissions
 - fossil fuels
 - Burning fuel and air


 

  organic molecules       