What is a characteristic feature of radionuclide decay?

The correct answer highlights a fundamental aspect of radionuclide decay, which is the emission of particles or radiation. In this process, unstable atomic nuclei lose energy by emitting radiation in the form of alpha particles, beta particles, or gamma rays as they transform into more stable configurations. This emission is a crucial characteristic of radioactive decay, as it is through this energy release that radionuclides move toward stability.

Radionuclide decay fundamentally changes the composition of the radioactive material, which is a critical point that differentiates it from other processes such as absorption of energy, stabilization of elements, or combination of elements. The emission of radiation is what makes radionuclide decay significant in various fields, including medical applications and nuclear energy, where controlling and understanding this emission is essential for safety and effectiveness.