Answer:
The deuterium-tritium (DT, Figure 2) reaction is the most useful for fusion energy because it most easily overcomes the Coulomb repulsion, and it has the highest energy release among laboratory-feasible reactions.
Step-by-step explanation:
When a deuterium nucleus (2H) and a tritium nucleus (3H) combine, the result is a helium nucleus and a very energetic neutron. Under the right circumstances, the energy released is sufficient to induce further fusion reactions.