All of the Following Are Ways in Which Cells Regulate

All of the following are ways in which cells regulate metabolism EXCEPT

A) isolation of various enzymes within membranous organelles.
B) synthesis of a catabolic enzyme only when its substrate is available.
C) use of the same coenzymes for anabolic and catabolic reactions that share substrate molecules.
D) feedback inhibition by end products.
E) synthesis or degradation of membrane transport proteins.