Burning fossil fuels increases the carbon in the atmosphere, and this atmospheric carbon might be contributing to the greenhouse effect. Given these facts, what is contributing to the greenhouse effect among the following options:
- energy of moving objects
 - mining gold
 - Warm air moving into cold air
 - burning fossil fuels
 - acid rain
 - melting ice caps
 - energy usage
 - single-celled organisms


 

    burning fossil fuels     