Describe the principle of radiation decay.

The principle of radiation decay refers to the process where an unstable atomic nucleus loses energy by emitting radiation in the form of particles or electromagnetic waves. This phenomenon occurs as the nucleus seeks to achieve a more stable configuration. The unstable atom can emit alpha particles, beta particles, or gamma rays, depending on the type of decay process involved.

Understanding radiation decay is crucial in fields like nuclear physics, medical imaging, and radiation therapy, as it helps explain how radioactive materials behave over time and how they can be monitored or used in various applications. The released energy during this decay process is a fundamental aspect of how radionuclides transform into more stable isotopes or elements, impacting both safety and utilization in various practical scenarios.

Overall, this principle underscores the nature of radioactivity as a means for unstable isotopes to alleviate their instability, which is encapsulated in the correct choice.