What is the purpose of the biogeochemical cycles?

a. to cycle energy through a food chain
b. to recycle matter through the biosphere
c. to recycle rocks through the layers of earth
d. to cycle nutrients through the human body

The purpose of the biogeochemical cycles is B. to recycle matter through the biosphere.
The geo part in the word makes D incorrect (because it deals with humans only, and not other inhabitants of the planet). It doesn't deal with food at all, so A is also incorrect. C is incorrect because the bio part means that there are beings involved, not only rocks. So B is correct because it encompasses all matter.

1. protection 2. homeostasis 3. storage4.blood formation5.bone marrow 6.movement