- The excretory system performs excretion
- Excretion is when the excretory system removes waste from the body
- Hence, the excretory system removes waste from the body

- The excretory system removes waste from the body
- Removing waste is a kind of function
- Hence, a function of the excretory system is removing waste from the body

Hence, a function of the excretory system is removing waste from the body
[Question]What is the major function of the human excretory system?
[Context]- Removing waste is a kind of function 
- The excretory system performs excretion 
- Excretion is when the excretory system removes waste from the body