You are presented with the question "Doing what to plants has a negative impact on the ecosystem?" and the following answer choices: 
- planting them
 - deforestation
 - cutting them down
 - Pesticides
 - watering them
 - massive damage
 - sitting under them
 - Abnormal cell growth

Now knowing that cutting down trees has a negative impact on an ecosystem and plants include trees, choose the best answer.


 

   cutting them down      