To find or discover by investigation?
To be referenced, it would be true
D, water vapor. Gaseous state would have more kinetic energy, they are moving faster. If you have to compare the same state, then higher temperature would have the higher kinetic energy. But if you have solid and liquid at the same temperature - then liquid would have more.
I think that the answe is gasses.
It is an example of reflection of wave. C.