What are the three states of matter?

The three fundamental states of matter are solid, liquid, and gas. These states are distinguished by their physical properties, including shape and volume.

In the solid state, matter has a definite shape and volume because the particles are tightly packed together, vibrating but not moving freely. This structure allows solids to retain a fixed form and only change shape under force.

In the liquid state, matter has a definite volume but takes the shape of its container. The particles are still close together but can move past one another, allowing liquids to flow and adapt to different shapes.

In the gas state, matter has neither a definite shape nor a definite volume. Gas particles are much farther apart and move freely and rapidly, which allows gases to expand to fill any container they occupy.

The other options include variations or specific examples that do not represent the fundamental states effectively. Ice is a specific form of a solid, while vapor refers more to the gaseous state of water, but they do not encompass all states of matter. Similarly, terms like gel and crystal refer to particular types of matter that fall into the broader categories but do not define the three basic states. Therefore, the correct answer encompasses the fundamental states of matter in their most basic form.