The figure shows the binding energy per nucleon of six nuclei against their mass numbers. The values are read straight from the figure. The total binding energy of a nucleus is its binding energy per nucleon times its mass number. Which of the following nuclear changes is described correctly, using only these values and no others?

Fig. 1: A graph of binding energy per nucleon in MeV, on the vertical axis from 0 to 10, against mass number from 0 to 250. The curve rises steeply for light nuclei, reaches a broad maximum near mass number 56, and falls slowly for heavy nuclei. Six points are marked and labelled with their values: H-2 at 1.11 MeV, He-4 at 7.07, C-12 at 7.68, O-16 at 7.98, Fe-56 at 8.79 and U-238 at 7.57.