How do the particles behave in a solid compared to a liquid?

In a solid, the particles are closely packed together and held in fixed positions by strong intermolecular forces. This arrangement allows the particles to vibrate around their fixed locations but prevents them from moving freely throughout the substance. This is why option A is accurate; it highlights that particles in a solid vibrate while maintaining their positions, leading to a stable shape and volume characteristic of solids.

Unlike solids, liquids have more energy in their particles, which allows them to overcome some of the intermolecular forces. This results in particles being able to slide past one another, leading to a more fluid shape while still maintaining a definite volume. Hence, the behavior of particles in liquids is characterized by more freedom of movement compared to solids, which is why the other options do not accurately describe solid behavior.