What is activation in a nuclear context, and what is a typical consequence for materials?

What is activation in a nuclear context, and what is a typical consequence for materials?

• A. Activation is the production of radioactive isotopes in materials by neutron irradiation, leading to residual radioactivity.
• B. Activation is the process of materials becoming superconductive under neutron exposure.
• C. Activation is the chemical reaction of materials with air causing corrosion.
• D. Activation is the expansion of materials due to neutron bombardment with no radioactivity.

Answer: (A)