Answer:
"A", "water changes from a gas to a solid to a liquid", according to this phase diagram, at at 0°C, as pressure is increased from 0atm to 10atm.
Explanation:
The question asks what happens at 0°C, as pressure is increased from 0atm to 10atm.
According to the question, the temperature is held constant. The pressure changes. In the phase diagram, we find the temperature 0°C on the horizontal axis, and all points where the temperature are 0°C are along that vertical line.
Since the pressure starts at 0atm and increases to 10atm, we start at the bottom, and move upward along that line, to see what phases of matter the substance changes to.
At the bottom, it is initially in a "gas" phase. As it moves up, it transitions to a "solid" phase. Later, as it continues moving up, it changes again into a "liquid" phase.
Thus, the answer would be "A", "water changes from a gas to a solid to a liquid", according to this phase diagram, at at 0°C, as pressure is increased from 0atm to 10atm.