Concept: In a solid, particles are tightly packed and only vibrate about their fixed positions.
Explanation:Particles in a solid do not have enough energy to move freely.
They are held together by strong intermolecular forces.
Therefore, they can only vibrate in place.
They do not show translational motion, because they cannot change position.
They also do not show random motion throughout the container.
Thus, the only motion exhibited is vibrational motion.
Answer: A. vibrational motion