The correct answer is B. Deliquescence.
Deliquescence is the property of a substance to absorb moisture from the air on exposure, and dissolve itself in the absorbed water. This is due to the fact that the substance has a high affinity for water molecules. When the substance comes into contact with water vapor in the air, the water molecules are attracted to the surface of the substance and form a layer of liquid. This layer of liquid dissolves the substance, and the resulting solution is then absorbed into the substance.
Osmosis is the movement of water molecules across a semipermeable membrane from an area of high water concentration to an area of low water concentration.
Efflorescence is the process by which salts crystallize on the surface of a material due to the loss of water of hydration.
Desiccation is the process of drying something out.