The correct option is D Evaporation
Evaporation is the process used to produce salt from sea water.
The seawater is collected in shallow pits or ponds near the sea-shore. These ponds are then exposed to sunlight for few days. The heat from the sun causes the water to evaporate, leaving behind a layer of sea salt crystals that can be harvested.
The salt crystals so obtained are collected and transported further to factories, where they are purified and packed for consumption.