Answer:
C. Magnesium
Step-by-step explanation:
Zinc sulphate (ZnSO4) will react fastest with Magnesium (Mg) because magnesium is more reactive than Zinc and other given elements.
Zinc sulphate (ZnSO4) reacts with Magnesium (Mg) and undergo displacement reaction. Zinc is displaced by magnesium and form Magnesium Suphate (ZnSO4).
ZnSO4 + Mg => MgSO4 + Zn