In a Michaelis-Menten plot, how does the presence of an uncompetitive inhibitor affect the curves?

• A. The curve shifts to the right, indicating an increase in Km.
• B. The curve remains unchanged.
• C. The curve shifts upwards, indicating an increase in Vmax.
• D. The curve shifts downwards, indicating a decrease in both Vmax and Km.

Answer: (D)