Evaluate the impact of a malfunction in ATP synthase on the proton motive force and ATP production.

• A. The proton motive force would remain the same, but ATP production would increase.
• B. The proton motive force would be unaffected, but ATP production would decrease.
• C. The proton motive force would increase, leading to more ATP production.
• D. The proton motive force would build up, but ATP production would decrease due to the inability to synthesize ATP.

Answer: (D)