What are the states of matter?

The states of matter encompass distinct physical forms in which matter exists, primarily classified as solid, liquid, gas, and plasma. In solids, particles are closely packed, vibrating in place and maintaining a fixed shape and volume. Liquids have more space between particles, allowing them to flow while maintaining a fixed volume but taking the shape of their container. Gases consist of widely spaced particles that move freely, occupying the entire volume of their container and having neither a fixed volume nor shape. Plasma, often considered the fourth state of matter, is a high-energy, ionized state where electrons are separated from atoms, commonly found in stars, including the sun.

This selection accurately reflects the four principal states of matter recognized in physics and chemistry. The inclusion of plasma is particularly important as it represents a state that is prevalent in the universe, even if it is less common on Earth compared to the other states. Other options either include terms that do not accurately represent distinct states of matter or combine states incorrectly, leading to confusion about the accepted classifications in scientific discourse.