Correct Answer - d
(d) Barium is not used in human body.
Calcium is useful in formation of bone teeth and helps in blood clotting. It keeps uscle and nerve activity normal. Phosphorus is important for formation of bone teeth and biomembranes. It keeps muscel and nerve activity normal. It is a part of energy carries (ATP, ADP,AMT) nuclei acid ( DNA and RNA) and coenzymes.
Zinc is a component of atleast 70 enzymes. It is also essential for vitamin A metabolism, healing of wounds and protein synthesis.
