ANS:B - increases

The boiling points of pure components of a binary system increase with an increase in the total pressure of the system. This phenomenon is described by Raoult's law, which states that the vapor pressure of each component of an ideal mixture is directly proportional to its mole fraction in the mixture and the vapor pressure of the pure component. When the total pressure of the system increases, the partial pressure of each component also increases. According to Raoult's law, this increase in partial pressure results in a higher boiling point for each component. In other words, the liquid must be heated to a higher temperature to reach the new, higher vapor pressure at the increased total pressure, causing the boiling points of the pure components to increase.