In the Nuclear Energy Curve Shown in the Graph Above

In the nuclear energy curve shown in the graph above, what quantity is graphed along the vertical axis?

A) the amount of thermal energy released [per nuclear particle] by nuclear reactions of each nucleus.
B) the amount of nuclear energy [per nuclear particle] in each nucleus.
C) Both of the above.
D) the amount of work required [per nuclear particle] to fuse or fission each nucleus.
E) All of the above.