Which statement describes why energy is released in a nuclear fusion reaction based on mass-energy equivalence?

In fusion, small nuclei combine to form a heavier nucleus with greater total binding energy than the starting nuclei had together. The increase in binding energy corresponds to a decrease in mass, and the missing mass is released as energy according to E = mc². So the correct statement is that the binding energy of the lighter nuclei is less than that of the heavier nucleus.

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