Which of the following is a chemical reaction?

Which of the following is a chemical reaction?

مندرجہ ذیل میں سے کون سا کیمیائی رد عمل ہے؟
Explanation

Rusting of iron is a chemical reaction where iron reacts with oxygen and water to form iron oxide (rust).

Unlike physical changes like melting or bending, rusting involves a chemical transformation.