There are reports of iron overdosage in the United States under 6 years of age and this is one of the common death due to poisoning. The red blood cells have hemoglobin which is a protein carrying oxygen to the cells in the body. The body then needs iron to produce hemoglobin. If one does not have iron, the red blood cells will become pale and smaller thus they cannot carry oxygen enough in the body.
I believe soccer is an aerobic exercise because your very reliant on air constantly jogging and sprinting. while anaerobic is a short lasting high intensity exercise not really reliant on oxygen. <span />
The correct answer would have to be C age.
Endurance is the answer i think you're looking for.