You are presented with the question "What has a positive impact on birds" and the following answer choices: 
- exercise
 - planting trees
 - recycling
 - community policing
 - food and shelter
 - with their fur
 - squirrels
 - four limbs

Now knowing that planting trees has a positive impact on an ecosystem and birds are important components of ecosystems, choose the best answer.


 

  planting trees       