Answer:
The integumentary system.
Explanation: The integumentary system is the on that is responsible for regulation and synthesis of the vitamin D. Remember this, Vitamin D for the skin is found when the sunlight has absorbed on the skin. Hope this helps!
C.) the process of bone remodeling ceases
the reason is because you don't reach full bone density till you are mid twenties and bone remodeling decreases from that time depending on how you preserve your bones.
Because whoever you hang with you become more like them
Answer:
D
Explanation regular physical activity can lower your risk for heart disease risk factor can be tobacco smoking; hypertansion
