Whether or Not an Enzyme Is Active and Present Within

Whether or not an enzyme is active and present within a cell depends on all of the following except

A) if the gene for the enzyme has been turned on and the enzyme made.
B) if the enzyme has been activated or inactivated by the addition of a phosphate group.
C) whether an inhibitor is bound to the enzyme.
D) whether the necessary cofactor is present.
E) whether the enzyme catalyzes an endergonic or exergonic reaction.