Why does a solid have a definite shape?

The particles of a solid cannot move at all.

The particles of a solid cannot change shape.

The particles of a solid have no forces of attraction between them.

The particles of a solid vibrate in fixed positions.

The correct answer is "The particles of a solid vibrate in fixed positions." In a solid, the particles are closely packed together and have strong forces of attraction between them. Although they do not move freely like in a liquid or gas, they do vibrate in their fixed positions. This vibration gives a solid its definite shape by maintaining the structural arrangement of the particles.