Which of the following is an example of a physical change?

A physical change is a transformation that does not alter the chemical composition of a substance. It typically involves a change in state or appearance without modifying the substance's molecular structure. The process of melting ice exemplifies this, as it transitions from solid to liquid while remaining water—its chemical identity stays intact.

In contrast, rusting of iron and burning wood involve chemical reactions that lead to the formation of new substances, such as iron oxide and ash, respectively. Cooking an egg also undergoes a chemical change, with the proteins denaturing and creating a different substance altogether. Therefore, melting ice is a clear instance of a physical change, as it showcases a reversible transformation without changing its chemical identity.