You are presented with the question "Which bodily system excretes a substance commonly used in drug testing?" and the following answer choices: 
- Evaporation
 - urinary system
 - animals
 - aqueous solution
 - cardiovascular system
 - opiate system
 - Integumentary system
 - sweating

Now knowing that urine is the liquid waste product of the body that is excreted by the urinary system and urine tests detect drugs used up to 36 hours before a given urine collection, choose the best answer.


 

  urinary system       