This nutrient is cycled between living things and the soil. Plants absorb this nutrient from the soil and turn it into organic c
ompounds through assimilation. Animals eats the plants and pass the nutrient through the food chain from one organism to another. When the animal dies, it decomposes and returns the nutrient back to the soil. The nutrient can also enter the soil through weathering and erosion.
It's not C or D because the Crust is actaully around 36km thick so that means it's eitehr A or B and the crust is mostly made form granite so Ima say B is the answer