On the Basis of the Surface and Atmospheric Conditions Existing

On the basis of the surface and atmospheric conditions existing on Mars today,why could there be no permanent liquid water on its surface?

A) The water would boil and evaporate rapidly under the low atmospheric pressure or freeze to ice at the low surface temperatures.
B) It would have reacted chemically with the surface rocks.
C) The UV radiation from the Sun would have dissociated the water molecules into hydrogen (which would leave the planet) and oxygen,which is still present.
D) It would have soaked into the porous surface of Mars.