A thin layer of zinc metal is used to coat iron surfaces in a process called galvanization. This layer protects the iron from rusting by acting as a barrier to moisture and air, and also because zinc is more reactive than iron, it undergoes corrosion first (sacrificial protection).
✅ Correct answer: zinc
The correct answer is zinc. Galvanizing is the process of coating iron with a thin layer of zinc to protect it from rusting. Zinc acts as a sacrificial metal, which corrodes instead of the iron, thus preventing rust formation on the iron surface. Therefore, the name of the metal 'X' is zinc.