Final answer:
C) Enzyme B (low activation rate). Considering activation energy and enzyme saturation kinetics, the reaction rates would be ranked as Enzyme B (the most product formed), followed by Enzyme A.
Step-by-step explanation:
To rank the reactions by the rate of product formation, we must consider the effect of activation energy and the presence of enzymes as catalysts. An uncatalyzed reaction with a super high activation rate normally proceeds slowly. Enzyme A has a middle activation rate, indicating it lowers the activation energy more than the uncatalyzed reaction but not as much as Enzyme B, which has a low activation rate and thus is the most efficient at increasing the reaction rate.
The rate of an enzyme-catalyzed reaction will initially increase with substrate concentration but will level off once all enzyme active sites are saturated; this is known as saturation kinetics. Conversely, an uncatalyzed reaction rate will continue to increase with the concentration of reactants due to the Law of Mass Action.
Considering these principles, the reactions can be ranked from the most product formed to the least product formed as follows: Enzyme B > Enzyme A > Uncatalyzed.