Please choose the correct answer to the question: Which best describes two organ systems working together to help maintain homeostasis?

Answer1: The reproductive organs produce sex cells. Answer2: The nerves carry signals from the eye to the brain. Answer3: The bones and muscles of the hand work together to grip a pencil. Answer4: The muscles of the chest tighten to push carbon dioxide out of the lungs.

Answer format: answer1/answer2/answer3/answer4