Which of the following statements is the major advantage of nuclear fusion over nuclear fission?

Analyze the question: It asks for the major advantage of nuclear fusion over nuclear fission, so we need to compare the two processes.

Concept:

• Fission: a heavy nucleus (e.g. Uranium-235) splits into smaller nuclei. It produces highly radioactive waste (fission products) that stays dangerous for thousands of years, and it releases neutrons that can trigger a chain reaction.
• Fusion: light nuclei (e.g. hydrogen isotopes, deuterium and tritium) join to form a heavier nucleus (helium). It needs extremely high temperatures (millions of °C), but its main product is helium, which is harmless. It produces little long-lived radioactive waste.

Checking each option:

• A. Fusion releases more energy: Per reaction, fission of one uranium nucleus releases more energy than one fusion reaction. Per unit mass of fuel, fusion releases more, but this is not the standard "advantage" the question is looking for. It is not the best choice.
• B. More neutrons released in fusion: Not true. Fission releases neutrons that sustain a chain reaction, and this is not an advantage.
• C. Fusion does not release as much dangerous radiation as fission: True. Fusion produces far less hazardous radioactive waste, so it is cleaner and safer. This is the major advantage.
• D. Fusion occurs more readily: False. Fusion needs extremely high temperature and pressure to overcome the repulsion between positively charged nuclei, so it is much harder to achieve.

Answer: The correct option is C.

Tip: Remember "Fusion = Fewer wastes, Fission = Fragments (dangerous waste)". When a question asks for the advantage of fusion, think "clean energy, little radioactive waste, abundant fuel (hydrogen)". Also remember that fusion is harder to start, not easier, which rules out D.