Most of the phosphorous on earth comes from:
rocks
water
the atmosphere
decaying organisms

rocks

Explanation:

Most of the phosphorus on earth comes from the rocks typically from the phosphate rocks. It takes millions of years to form these rocks under the surface of the earth crust. The rocks are typically formed by the geological processes in the geosphere. The largest sources of the phosphorus comes from the sedimentary rocks. This can be found in the sediments found over the oceanic floors. The phosphorus can also be found in the animals, humans, soil and in plants.

i believe the answer is c