Final answer:
The melting point of albite with water decreases by 220 degrees Celsius as the depth of its burial increases from 0 to 3 km, due to increased pressure at greater depths.
Step-by-step explanation:
The question asks how the melting point of albite with water changes as it is buried from 0 to 3 km depth. Referring to the phase diagrams provided, the melting point of water decreases with increasing pressure. A similar effect would occur with albite in the presence of water under high-pressure conditions. As depth increases, the pressure on the albite also increases. Since increasing pressure on ice, which is less dense than water, causes it to melt at lower temperatures, we can conclude that albite's melting point would behave similarly and decrease. Therefore, the correct answer to the question is It decreases by 220 degrees Celsius.