Final answer:
The properties of solids, liquids, and gases - like shape, volume, and compressibility - are determined by the arrangement and movement of their particles.
Step-by-step explanation:
The observable functions and properties of solids, liquids, and gases are intrinsically related to the structure of particles that compose the substances. Solids have particles that are closely packed in a fixed arrangement, which gives them a definite shape and volume and makes them incompressible. On the other hand, liquids have particles that are close together but not in a fixed arrangement, allowing them to flow and take the shape of their container, although they are still nearly incompressible. Gases have particles that are far apart and move freely, which means they have no definite shape or volume and can be compressed significantly. Therefore, the correct answer to the question is that solids hold their shape; gases can be compressed.