6. Which is a skeletal muscle? A. arm muscle B. heart muscle C. eye muscle D. all of the above 7. What is the main function of the muscular system? A. protection B contraction C. attachment D. locomotion 8. Which can be done without the use of muscles? A jumping B. swimming C. digestion D. none 9. What connects the skeletal muscle to the bone ? A ligaments B tendons C. origin​