Which of the Following Statements Is MOST Accurate Concerning Metabolism

Which of the following statements is MOST accurate concerning metabolism?

A) Metabolism is the production and expenditure of chemical energy.
B) Metabolism is the assembly of small molecules into macromolecules.
C) Metabolism is the digestion of nutrients to release energy.
D) Metabolism is all the chemical reactions of an organism, both anabolic and catabolic.
E) Metabolism is the assembly of macromolecules into cellular structures.