What physical state of matter has a definite shape and volume?

In the context of the states of matter, solids are characterized by having both a definite shape and a definite volume. This means that unlike gases, which spread to fill their container, or liquids, which take the shape of their container while maintaining a consistent volume, solids maintain their shape regardless of the environment they are in. This structure comes from the tightly packed arrangement of their molecules, which are held together by strong intermolecular forces, allowing solids to retain their form and volume.

Plasma, while being a state of matter, does not have a definite shape or volume; instead, it consists of ionized particles that can spread out to fill a space, much like gases. Therefore, among the given options, solids uniquely possess both a definite shape and a definite volume.