Question

n + energy
⁴he + energy
nuclear fission because an atom is splitting into two fragments
nuclear fusion because the products that are produced are radioactive
nuclear fission because a large amount of energy is being released
nuclear fusion because atomic nuclei combine to form a heavier nucleus

Explanation:

To determine the correct option, we analyze nuclear fusion and fission:

• Nuclear fission is the splitting of a heavy nucleus into smaller fragments.
• Nuclear fusion is the combination of lighter atomic nuclei to form a heavier nucleus, releasing energy.

In the diagram, atomic nuclei (like hydrogen isotopes, likely deuterium/tritium) combine to form a heavier nucleus ($^4$He, helium - 4) along with a neutron and energy. This matches the definition of nuclear fusion.

• Option 1: Fission involves splitting, not what's shown.
• Option 2: Radioactivity of products isn't the defining factor of fusion.
• Option 3: Both fission and fusion release energy; the key is the process (combination vs. splitting).
• Option 4: Correctly describes fusion as nuclei combining to form a heavier nucleus.

Answer:

nuclear fusion because atomic nuclei combine to form a heavier nucleus