Which of the following are the basic states of matter?

• A. Solid, Liquid, Gas
• B. Energy, Force, Motion
• C. Mass, Volume, Density
• D. Atoms, Molecules, Ions

Answer: (A)

The basic states of matter are solid, liquid, and gas. Each state describes how particles are arranged and how they move, which determines shape and volume. In a solid, particles are tightly packed and vibrate in place, giving a definite shape and volume. In a liquid, particles are less tightly held, slide past each other, so it keeps a definite volume but takes the shape of its container. In a gas, particles are far apart and move freely, filling both the space and the volume available, and they are easily compressible. An ice–water–steam progression is a familiar way to see the same substance in different states.

The other options don’t describe states of matter. Energy, force, and motion are about how matter or systems behave, not the distinct forms matter can take. Mass, volume, and density are properties of matter, not its states. Atoms, molecules, and ions are the building blocks of matter, not the states themselves.