Which statement best describes energy coupling?

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Energy coupling in metabolism involves using energy released by an exergonic process to drive an endergonic one. When these steps are linked, their free-energy changes add up. If the exergonic step provides enough energy, the total ΔG becomes negative, so the overall process can proceed spontaneously. In cells, ATP hydrolysis is the common exergonic source, transferring energy to drive biosynthetic or mechanical tasks, often through phosphorylation or energy transfer within enzyme complexes.

This description fits best because it captures how endergonic reactions are powered by energy release from exergonic reactions, producing an overall negative ΔG. The other ideas don’t describe the mechanism: energy coupling doesn’t slow endergonic reactions, it doesn’t halt energy flow, and it doesn’t render the overall process endergonic; it makes the combined process favorable.