Galvanization is a process in which a protective  ___________ coating is applied on iron to prevent it from rusting.

zinc

The correct answer is option 2. zinc.

Galvanization is a process in which a protective zinc coating is applied to iron to prevent it from rusting.

Zinc coating acts as a sacrificial anode, providing cathodic protection to the iron underneath. This means that even if the zinc coating gets scratched or damaged, the iron underneath remains protected because the zinc will corrode preferentially, sacrificing itself to protect the iron from rusting.