What conclusion is best supported by the decay chain?
A) Each alpha decay results in an isotope that is slightly more stable than the original isotope.
B) Each beta decay results in an isotope that is slightly more stable than the original isotope.
C) The atomic number increase caused by two beta decays is the same as the decrease caused by one alpha decay.
D) The mass number increase caused by two beta decays is the same as the decrease caused by one alpha decay.