Q: What has a special excretory structure?
Options:
- (A) Silk plants.
- (B) Insects.
- (C) a fish
- (D) animals
- (E) plants
- (F) Architecture structures.
- (G) barnacles
- (H) Corset structure.
A: (B)
Explain how we arrive at this answer: 
Explanation: Some arthropods have special excretory structures. All insects are arthropods. Insects have special excretory structures.