You are presented with the question "Burning carbon concentrations have what?" and the following answer choices: 
- Greenhouse gases
 - Chemical energy
 - reduced significantly
 - increased dramatically
 - Plant growth is reduced
 - heat energy
 - shrunk
 - declined spectacularly

Now knowing that carbon dioxide concentrations in the air have increased over the last decade dramatically and carbon dioxide is formed by burning carbon, choose the best answer.


 

    increased dramatically     