It is the inherent quality of matter tom expand on being heated.

eternal
hidden
internal
natural

The correct answer is D.

natural.

The expansion of matter on being heated is a natural phenomenon. It is a result of the increase in the kinetic energy of the molecules of matter. When matter is heated, the molecules move faster and have

more energy. This causes them to take up more space, which is why matter expands on being heated.

The other options are incorrect.

  • Eternal means lasting forever. This is not the case for the expansion of matter on being heated. It is a temporary phenomenon that occurs when matter is heated.
  • Hidden means not visible or not easily understood. The expansion of matter on being heated is a visible phenomenon that is easily understood.
  • Internal means located or occurring inside something. The expansion of matter on being heated is a phenomenon that occurs on the surface of matter.

I hope this helps! Let me know if you have any other questions.