As we can see, molecules of substance A are more distant from each other, while that of substance b are closer and substance c are very close.
We can therefore assume that substance A is in the gaseous state, substance b is in the liquid state and substance c is in the solid state.
In the solid state, the shape and volume are well defined. In the liquid state, shape and volume are more or less defined, whereas in the gaseous state, shape and volume are not defined.
Substances in the gasous and liquid state will react to the increased volume of space.
Answer: Alternative "A"