Personally, I think sport is all about having fun so D. But if your client is trying to loose weight, then A and B because you want to vary it!
cells have many structures inside of them called organelles. these organelles are like the organs in a human and they help the cell stay alive. each organelle has it's own specific function to help the cell survive. the nucleus of a eukaryotic cell directs the cell's activities and stores DNA.
The answer is a, medial. Medial means toward the midline (or middle) of the body. The heart is closer to the midline of the body in comparison to the shoulder.
Answer - Blood Flow
Reasoning - Insulin is used through out and mainly in the blood stream which relies it to stabilize through out the flow of the body