Biogeochemical Cycles Can Be Described as __________________

Biogeochemical cycles can be described as __________________.

A) Circulation of chemical elements exclusively through the biotic portions of the biosphere
B) Recycling of essential elements directly between living organisms
C) Use of biochemical reactions in microbes to change unusable forms of elements from the physical environment into chemical forms that can be metabolized by other living organisms
D) Circulation of chemical elements exclusively through the abiotic portions of the biosphere