Your answer is A. Parasitism :)
It forms in lagoons where ocean waters high in calcium and sulfate content can slowly evaporate and be regularly replenished with new sources of water. The result is the accumulation of large beds of sedimentary gypsum. Gypsum is commonly associated with rock salt and sulfur deposits.
An earthquake is the sudden release of energy from the crust of the Earth, that results in a seismic wave. Using a seismograph, the interior of the Earth is mapped, finding the epicenter (origin) and magnitude (strength) of the quake.
Sleep is an example.
Circadian rythms are biological processes that repeats itself within a certain time frame, as sleep repeats itself approximately once every day.