What type of radioactive decay involves capturing an electron?

The correct response, electron capture, refers specifically to a type of radioactive decay where an inner-shell electron is captured by the nucleus of an atom. This process results in the conversion of a proton into a neutron, thus transforming the original atom into a different element with a lower atomic number.

In electron capture, the absorption of the electron leads to a net decrease in the positive charge of the nucleus, facilitating the change in atomic identity without the emission of particles, which is distinct from other decay processes. The result of this decay can lead to a more stable nuclear state, as it often occurs in isotopes that have too many protons compared to neutrons.

This mechanism is critical to understanding how certain isotopes behave and stabilize over time, playing a significant role in the study and application of radioactive materials in various scientific fields.