Unlike the carbon cycle, the phosphorous cycle does not involve
a. geological processes.
b. chemical and physical processes.
c. human activity.
d. was biological processes.

The phosphorus cycle is a natural cycle that occurs through rocks, water, soil, sediments, and other organisms found on Earth. Phosphorus is a natural chemical compound found in soil; rain and other forms of weathering causes the release of this compound in the environment. Plants absorb phosphorus from the soil and in turn are consumed by animals and humans. This chemical compound is an essential form of nutrient that is responsible for cell development both in humans and animals.

Unlike the carbon cycle, the phosphorus cycle does not need the involvement of human activity for it to occur. But humans take advantage of this naturally occurring process through farming. Humans apply phosphate fertilizers to their crops in various farmlands. 

Ichoose a as my answer