Which of the following remains constant in Earth's carbon cycle?
A B C D
the total mass of available carbon the way organisms use carbon the physical state of carbon-containing molecules the molecule in which a particular carbon atom is found
Question: Which of the following remains constant in Earth's carbon cycle?
(A) the total mass of available carbon
(B) the way organisms use carbon
(C) the physical state of carbon-containing molecules
(D) the molecule in which a particular carbon atom is found

Answer: (A) the total mass of available carbon
Answer: (C) the physical state of carbon-containing molecules
Question: Which of the following remains constant in Earth's carbon cycle?
(A) the total mass of available carbon
(B) the way organisms use carbon
(C) the physical state of carbon-containing molecules
(D) the molecule in which a particular carbon atom is found
Answer: (A) the total mass of available carbon