The correct statement that characterizes an atomic attribute suitable for applications in nuclear medicine and nuclear power generation is:
Isotopes of an element vary in the quantity of neutrons they possess. Certain unstable isotopes are utilized in the fields of nuclear medicine and nuclear power generation.
Unstable (radioactive) isotopes are primarily used for their radioactive properties in both nuclear medicine (such as in imaging and therapeutic applications) and in nuclear power generation (where they undergo fission to produce energy).