The correct answer is B. Iron.
Haemoglobin is a protein found in red blood cells that carries oxygen from the lungs to the rest of the body. It is made up of four subunits, each of which contains a heme group. The heme group is a complex of iron and protoporphyrin IX. The iron in the heme group is what binds to oxygen.
Copper, manganese, and zinc are all essential minerals for human health, but they are not found in haemoglobin. Copper is involved in many important bodily functions, including the production of red blood cells. Manganese is involved in bone formation and energy production. Zinc is involved in immune function and wound healing.
Haemoglobin is a complex protein that is essential for human life. It is made up of four subunits, each of which contains a heme group. The heme group is a complex of iron and protoporphyrin IX. The iron in the heme group is what binds to oxygen.