7. All living things are constantly faced with the situation of adjusting to their changing environment. What human body system controls, regulates and coordinates most of our body function with this changing environment? A. circulatory B. digestive C. nervous D. respiratory 8. It is responsible for the breathing and controlling our speech. A. brain B. heart C. neuron D. spinal cord 9. The system is composed of the brain, neurons, and the spinal cord. A. circulatory B. digestive C. nervous D. respiratory 10. It is an illustration of human nervous system. ttps://qbiuq.edu.au/brain/brain B. C. https://www.thoughtco.com/respiratory https://americanaddictioncenters D. https://www.progressivenutr