we need a better understanding of this question
The Skeletal system in the body is in between the skin/muscle tissue, and the organs. Our bones offer protection to most of our vital organs.
ex: our skull protects our brain and our chest plate protects our heart and lungs.
B/C (aerobic exercise strengthens heart & lungs)
Jerry's goal is to increase his arm strength look at these entries in his workout log and determine which principles of training is he most likely focusing on in order to reach that goal.
Jerry is focusing on doing reps to improve his arm strength.