Which statement best describes alpha decay?(1 point) After the ejection of an alpha particle, the remaining nucleus has a mass number that is two less and an atomic number that is two less, so alpha decay is a type of nuclear fission.

After the ejection of an alpha particle, the remaining nucleus has a mass number that is two less and an atomic number that is two less, so alpha decay is not a type of nuclear fission.

After the ejection of an alpha particle, the remaining nucleus has a mass number that is four less and an atomic number that is two less, so alpha decay is a type of nuclear fission.