Uses of artificial radioisotopes: which of the following applications legitimately use artificially produced radioactive isotopes?

Introduction / Context:
Artificial radioisotopes—nuclides produced in reactors or accelerators—are widely used across medicine, industry, research, and power applications. Recognizing the breadth of their applications is essential for engineering awareness and public policy discussions on nuclear technology.

Given Data / Assumptions:

• Artificial radioisotopes include medical isotopes (e.g., I-131, Tc-99m), industrial sources (Co-60), and special-purpose nuclides (Pu-238 for radioisotope power systems).
• “Power generation” here includes radioisotope thermoelectric generators (RTGs) and heater units, not just fission reactors.
• “Initiating fission/fusion” includes neutron sources (e.g., Am-Be) and tritium for fusion research.

Concept / Approach:
Each listed domain has well-established uses: RTGs provide long-lived electrical power for spacecraft; radiotherapy and imaging rely on specific isotopes; neutron sources and tritium support fission startup, calibration, and fusion experiments. Hence, artificial isotopes are legitimately used in all the listed ways.

Step-by-Step Solution:

Verification / Alternative check:
Review of mission profiles (e.g., Voyager, Curiosity) shows RTG use; standard hospital radiopharmacies dispense artificial isotopes; reactor startups and research labs use sealed neutron sources and tritium handling systems.

Why Other Options Are Wrong:

• Any single item alone omits other legitimate uses.
• “None of the above” contradicts extensive practice.

Common Pitfalls:
Thinking “power generation” must mean grid-scale fission reactors only; overlooking that RTGs are genuine power systems driven by radioactive decay heat.

Final Answer:
All of the above