You are presented with the question "What has a special excretory structure?" and the following answer choices: 
- Silk plants.
 - Insects.
 - a fish
 - animals
 - plants
 - Architecture structures.
 - barnacles
 - Corset structure.

Now knowing that some arthropods have special excretory structures and all insects are arthropods, choose the best answer.


 

  Insects.       