option c. freeze-drying technology dehydrates foods through sublimation
Sublimation is one of the example, in freezing, it needs to cool it down first. If there is some water in some food, this water becomes ice. Then take away the air around that you want to freeze-dry, this reduces the pressure a lot. The boiling point of water drops when you reduce pressure, so when you drastically reduce pressure to almost zero it eventually drops below the temperature of the frozen food. This effectively makes the solid ice in the food "boil" or sublimate, it becomes a gas without first becoming a liquid.
We could describe this process using a picture of water-molecules as particles so you could for example first draw water molecules in a crystal structure with air particles above it which keeps the water particle in a crystal. Then you could draw another picture with no air particles and some water particles escaping the crystals in all directions like a gas like sublimation.