Answer:
A. Regular participation in physical activity reduces the risk of developing various diseases
Answer:
cranial nerves, spinal nerves and their roots and branches, peripheral nerves, and neuromuscular junctions
Explanation:
The answer is body's line of defense. The first line of defense which includes physical as well as chemical barriers would defend the body from infection. It would include the tears, cilia, stomach acid,urine, white blood cells,mucus and the skin. The skin is the largest organ and would act as a barrier from pathogens. If first line of defense won't work the second line will then be activated.