Fact 1: Some arthropods have special excretory structures.

Fact 2: Arthropods contain jointed appendages.

Given the two facts above, answer the question "Some animals with jointed what have special excretory structures" with the following options: 
- skin
 - appendages
 - they bend
 - eyes
 - muscles
 - sensory neurons
 - organ
 - insects


 

  appendages       