The kinetic energy of the solid decreases. The average density of the solid increases. The specific heat capacity of the solid decreases. The average molecular speed in the solid increases.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which of the following changes occurs as a solid is heated?
Possibilities:
- The kinetic energy of the solid decreases.
- The average density of the solid increases.
- The specific heat capacity of the solid decreases.
- The average molecular speed in the solid increases.

The average molecular speed in the solid increases.