When an Enzyme Is Saturated It

When an enzyme is saturated it

A) has been completely consumed,and that reaction cannot occur again until new enzymes are produced.
B) is in high concentration relative to the substrate,and the reaction rate is directly proportional to substrate concentration.
C) is in low concentration relative to the substrate,and the reaction rate is directly proportional to enzyme concentration.
D) is in low concentration relative to the substrate,and the reaction rate approaches its maximum.
E) none of the above