You are presented with the question "What causes pink flamingos' population to decrease?" and the following answer choices: 
- replenishing their habitats
 - drought
 - harming them
 - hypothyroidism
 - helping them
 - influenza
 - feeding them
 - Pesticides

Now knowing that harming an animal species causes that animal 's population to decrease and today, the pink flamingo is included on the endangered species list, choose the best answer.


 

   harming them      