Answer:
The best answer to the question: What would happen to the proton gradient and ATP production after a drug has poisoned the enzyme that combines acetyl CoA and oxaloacetate to form citrate? Would be, C: Less NADH production would create to a weaker proton gradient and less ATP production.
Explanation:
The reason comes from remembering that ATP is a molecule that is produced when protons are transferred in a chemical reaction called anabolism to the precursor for ATP, ADP. This process of transference of protons requires the correct work of several chemical compounds, including enzymes and coenzymes, which basically assist enzymes in the management of hydrogen atoms during metabolic processses.
NADH, like others, is a coenzyme whose task is to accept hydrogen atoms and assist in the oxidation-reduction reactions that take place in the body, including the production of ATP. If a poison has stopped the correct transfer of protons by preventing the correct work of both enzymes and coenzymes, then the direct result is the lesser production of NADH and therefore there will be a much less efficient process of proton transfer to produce ATP.