Evaporation is different than precipitation in that:

a. evaporation is a product and precipitation is the process.

b. evaporation is necessary to the water cycle and precipitation is not always necessary.

c. evaporation requires precipitation but precipitation does not require evaporation.

d. evaporation is a process and precipitation is more of an element in that process.

The answer is D.

Evaporation is the process of a liquid's surface changing to a gas. In the water cycle, liquid water evaporates and becomes water vapor.  The water cycle's evaporation process is driven by the sun and influenced by wind, temperature, and the density of the body of water.

Precipitation  unlike evaporation is not a process. Precipitation describes any liquid or solid water that falls to Earth as a result of condensation in the atmosphere. Precipitation includes rain, snow, and hail.

Therefore precipitation is an element in the process of the evaporation.