Which of the following is true about melting point of a liquid?

• A.The presence of dissolved impurities increases the melting of a pure solid
• B.An increase in pressure decreases the melting point of a substance that contracts in volume on freezing , more than the one that expands in volume
• C.The melting point is not the same as the solidification of a substance.
• D.The presence of the dissolved impurities does not change the melting point of a pure solid.