All of the Following Are Aspects of a Cell's Ability

All of the following are aspects of a cell's ability to regulate its metabolism EXCEPT

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