Frank is trying to model how the body works when an athlete runs a 10-kilometer race. He includes several body systems in his model. Frank includes the muscular system because it coordinates with the skeletal system to create the physical motion of running. He also includes the nervous system because it sends the electrical and chemical messages to the arms and legs signaling them to move. Frank also adds the circulatory system because it works to pump more oxygenated blood to the cells during the run. Which of the following is illustrated by Frank's model? A. The muscular system is the most important system needed to run. B. Multiple systems of the body must interact to carry out the functions needed to run. C. Only one body system can work at a time to carry out the functions needed to run. D. Body systems do not interact with each other to carry out the functions needed to run.
