In which of the following spheres of earth is most carbon stored long-term? a- atmosphere b-biosphere c- cryosphere d- geosphere

Carbon is the fourth most abundant element. It is  the building block of life on Earth. The Geosphere is the sphere of Earth in which the most carbon stored long-term D
The Geosphere carbon cycle operates at very long, slow time scales of thousands to millions of years.

The endocrine system is made up of glands that produce and secrete hormones, chemical substances produced in the body that regulate the activity of cells or organs. These hormones regulate the body's growth, metabolism (the physical and chemical processes of the body), and sexual development and function.