Which Statement BEST Describes the Relationship Between an Enzyme and a Reactant

Which statement BEST describes the relationship between an enzyme and a reactant?

A) The relationship is temporary.
B) Covalent chemical bonds stabilize the relationship.
C) The enzyme and the reactant molecule are both permanently changed.
D) The resultant product and the enzyme are permanently bonded together.
E) The reactant cannot function without the enzyme.