What state of matter has molecules that can move around each other?

In the context of states of matter, liquids are characterized by having molecules that can move around each other while still maintaining a definite volume. This ability to flow is due to the relatively weak intermolecular forces in liquids compared to solids. In a liquid, molecules are close together but are not fixed in place; they can slide past one another, which allows the liquid to take the shape of its container.

In contrast, solids have tightly packed molecules that cannot move freely, which gives them a fixed shape and volume. Gases consist of molecules that are far apart and move independently of one another, filling the entire volume of their container, while plasmas are high-energy states where electrons are stripped from atoms, leading to a collection of charged particles. Therefore, the distinctive property of liquids is their ability to allow molecules to move past each other, making them the correct choice for this question.