Answer: The correct answer is "Tightly-packed particles gain energy, allowing them to move more freely".
Explanation:
The three states of the matter are: Solid, liquid and gas.
Solid: In the solid state, the particles are tightly packed. The particles of the solid are not free to move. Solids are rigid. They have definite shape and volume.
Liquid: In the liquid state, the particles are loosely packed in comparison to solid. The particles of the liquid are free to move. They do not have definite shape.
Gas: In the gaseous state, the particles are more loosely packed in comparison to liquid. The particles of the gas are more free to move. They do not have definite shape.
In the given photograph, matter is changing its state. Here, ice is solid and it is changing its state. It starts melting after gaining energy from the surrounding. Then, the particles can move more freely.
Therefore, the correct option is "Tightly-packed particles gain energy, allowing them to move more freely".
