Rover Opportunity Discovered Martian Rocks with Polygon-Shaped Cracks

Rover Opportunity discovered Martian rocks with polygon-shaped cracks. One theory is that an impact released water from the Martian soil to flood these rocks. Water seeped into the rocks, froze, and caused the cracks. This explanation requires large amounts of water for several reasons. Which of these is NOT one of these reasons?

A) The surface temperature on Mars is always below the freezing point of water.
B) Much of the water thus liberated would be vaporized by the impact.
C) Liquid water on the surface of Mars would vaporize because of the low pressure.
D) Such rocks have been discovered at widespread locations on Mars.