From the given graph, it can be seen the representation of the process of going from one state of matter to other one.
For both A and B, they start at a solid state.
Then, they go through a fusion process and became liquids.
After that, they suffer vaporization and turn into gases.
From this, we can conclude that the states of matter shown are gas, liquid and solid.
The correct answer is D) gas, liquid and solid.
