Evaporation is defined as:
A. conversion of ice in the water
B. conversion of water into water vapors
C. conversion of water vapour into water
D. freezing of water into ice

Hint: In the evaporation process, the compound in the liquid form changes its state to gaseous form. The process of evaporation can be seen in the ocean near the equator as the evaporation rate is higher near the equator. Salt is the by-product of evaporation in seawater.

Complete step by step answer:
When the compound in solid state changes to a liquid state, the resulting process is called melting.
Example: melting of ice- ice on increasing temperature starts melting and changes to water.
When water is heated, it slowly starts evaporating and changes its state from liquid to water vapors below the boiling point temperature of the water. This process is known as evaporation.
Example: boiling of water- On boiling water, the water changes to water vapor.
When the water vapors change its state from gas to liquid, the process is known as condensation.
Example: Morning dew-the moisture in the air condenses into water droplets and deposit in the grass.
When the compound in liquid state changes to solid state, then the process is known as freezing.
Example: Freezing of water- when water is frozen it changes to ice.
Thus, evaporation is defined as the conversion of water into water vapors.

So, the correct answer is “Option B”.


Note:
There is a difference between the process of evaporation and boiling as the boiling point of water is $100^\circ C$(212 degree Fahrenheit) but the evaporation of water starts at the temperature of $0^\circ C$(32 degree Fahrenheit). The evaporation process is a very slow process.