You are presented with the question "What can have a negative impact on a species' population size?" and the following answer choices: 
- cigarettes
 - Pesticides
 - steroids
 - humans
 - weather
 - flooding
 - Smoking
 - viruses

Now knowing that harming an animal species has a negative impact on the population size of that species and hot weather can cause harmful bacterial growth in feeders, choose the best answer.


 

     weather    