The Following Diagram Shows a Close-Up View of the Vapor

Multiple Choice

The following diagram shows a close-up view of the vapor pressure curves for a pure solvent and a solution containing a nonvolatile solute dissolved in this solvent.
-Which curve is the solvent and what happens to the vapor pressure when the solute is dissolved in the solvent?

A) Curve (a) is the solvent and the vapor pressure decreases.
B) Curve (a) is the solvent and the vapor pressure increases.
C) Curve (b) is the solvent and the vapor pressure decreases.
D) Curve (b) is the solvent and the vapor pressure increases.