Answer: Option (b) is the correct answer.
Explanation:
In a solid, molecules are held together by strong intermolecular forces of attraction. As a result, they are unable to move from their initial place but they can vibrate at their mean position.
Hence, in solid substances the molecules have low kinetic energy.
Whereas in liquids, the molecules are held by less strong intermolecular forces of attraction as compared to solids. Due to which they are able to slide past each other. Hence, they have high kinetic energy as compared to molecules of a solid.
Therefore, as sample D is retaining its shape so, it is a solid.
Thus, we can conclude that the statement D is a solid because it retains its shape correctly describes the state of matter of one of the samples.
