Answer the following question given this paragraph: 

Some arthropods have special excretory structures. They are called coxal glands and Malphigian tubules. Coxal glands collect and concentrate liquid waste from blood. They excrete the waste from the body through a pore. Malphigian tubules carry waste from the digestive tract to the anus. The waste is excreted through the anus.


Q: In arthropods, coxal glands and malphigian tubules perform what role?

 Choices:

- ingestion

- reproduction

- photosynthesis

- excretion

A:
excretion
