The statement that best describes how iron helps the body maintain homeostasis is A. It helps red blood cells carry oxygen. Iron is a vital mineral that is required for the production of hemoglobin, a protein in red blood cells that carries oxygen from the lungs to other parts of the body. Iron also plays a crucial role in the production of myoglobin, a protein that stores oxygen in muscle tissue. Without iron, the body cannot produce enough red blood cells to transport oxygen, leading to anemia and other health problems. Therefore, iron is essential for maintaining homeostasis in the body by ensuring that all organs and tissues receive the oxygen they need to function properly.