When a Radioactive Isotope Decays by Electron Capture, the Electron

Multiple Choice

When a radioactive isotope decays by electron capture, the electron _________.

A) combines with a neutron in the nucleus, raising the mass number of the daughter isotope by one
B) makes the daughter isotope into an ion with a charge of positive one
C) combines with a proton in the nucleus; the atomic number of the daughter is one less than the parent
D) makes the parent isotope into an ion with a charge of negative one