Long hair is cut and dried. A wooden pencil is sharpened and breaks. An ice cube melts and becomes a clear liquid. An iron nail becomes orange and flaky on the surface.
Which action demonstrates a chemical change?

Options:
- Long hair is cut and dried.
- A wooden pencil is sharpened and breaks.
- An ice cube melts and becomes a clear liquid.
- An iron nail becomes orange and flaky on the surface.

An iron nail becomes orange and flaky on the surface.