23. When a nonvolatile solute is added to a volatile solvent, the solution vapor pressure , the boiling point _, the freezing point _, and the osmotic pressure across a semipermeable membrane . (A) decreases, increases, decreases, decreases (B) increases, increases, decreases, increases (C) increases, decreases, increases, decreases (D) decreases, decreases, increases, decreases (E) decreases, increases, decreases, increases