What are the three states of matter?

The correct answer identifies the three classic states of matter: solid, liquid, and gas.

In a solid, the particles are closely packed together in a fixed arrangement, which gives it a definite shape and volume. In liquids, the particles are still close together but can move past one another, allowing liquids to take the shape of their container while maintaining a fixed volume. Gases have particles that are far apart and move freely, meaning they can expand to fill the entire volume of their container, showing no fixed shape or volume.

The other options include combinations that either introduce states not typically categorized as fundamental states of matter, such as plasma and crystal, or include terms that represent specific conditions or phases but do not encompass the foundational three states recognized in classical physics.