You are presented with the question "Releasing what can have a negative impact on an ecosystem?" and the following answer choices: 
- disease
 - viruses
 - A virus
 - Carbon
 - tar
 - toxins
 - herbicide
 - vehicles

Now knowing that cutting down trees has a negative impact on an ecosystem and if trees are cut or burned, the carbon is released back into the atmosphere, choose the best answer.


 

    Carbon     