Which state of matter is characterized by having a definitive shape and volume?

The state of matter characterized by having a definitive shape and volume is a solid. In solids, the particles are closely packed together in an orderly arrangement, which gives them a fixed shape and volume. This structural integrity means that solids maintain their form without the need for a container, unlike liquids and gases, which conform to the shape of their containers and can change volume.

In liquids, while they have a definite volume, they do not have a definitive shape; they take the shape of the container they are held in. Gases, on the other hand, do not have either a fixed shape or volume and will expand to fill whatever space is available. Plasma, which is an ionized state of matter found in stars and certain types of lighting, also does not maintain a definitive shape or volume.

Thus, the distinction of solids having both a definitive shape and volume is what makes this choice the correct answer.