Carbon atoms are the basis for all life on earth. Carbon atoms are found in all the molecules that make up living organisms—carbohydrates, lipids, proteins, and nucleic acids. Why is carbon important in the earth’s ecosystems?
A. Carbon originates in sunlight.
B. Carbon is produced in the nitrogen cycle.
C. Carbon atoms are found in molecules of all living organisms.
D. Carbon atoms are found only in nonliving matter.