What state of matter takes the shape of its container but has a fixed volume?

The state of matter that takes the shape of its container but has a fixed volume is liquid. In this state, molecules are close together but can move past each other, allowing liquids to flow and adapt their shape to fit the confines of their container. However, the volume of a liquid remains constant regardless of the shape of the container it occupies.

In contrast, solids have a definite shape and volume due to their tightly packed molecules that can only vibrate in place. Gases take both the shape and volume of their container, as their molecules are far apart and move freely. Plasma, a state of matter found at high temperatures where electrons are stripped from atoms, does not have a fixed shape or volume either and is less commonly encountered in everyday life compared to solids, liquids, and gases. Therefore, the correct identification of a liquid as the state of matter that maintains a fixed volume but conforms to the shape of its container clearly sets it apart from the other options provided.