carrying oxygen to the lungs sending signals from the brain to the spinal cord breaking down food into nutrients providing support for the body
I gave my students this multiple choice question: Which of the following is a function of the digestive system of the human body?

Only one answer is correct among these 4 choices:
- carrying oxygen to the lungs
- sending signals from the brain to the spinal cord
- breaking down food into nutrients
- providing support for the body

Could you tell me which one is correct?

breaking down food into nutrients