Correct option is D
A – II (Mg): Magnesium plays a key role in ATP formation, making it an energy carrier.
B – IV (Mg): Also, Mg is the central atom in the chlorophyll molecule.
C – I (Mo): Molybdenum is essential for the nitrate reductase enzyme in nitrogen metabolism.
D – III (Zn): Zinc deficiency causes Khaira disease in rice, characterized by chlorosis and stunted growth.