In what type of radioactive decay does the atomic number of the product decrease by one? select all that apply.
a. alpha emission
b. beta emission
c. gamma emission
d. positron emission
e. electron capture

The atomic number of the product decrease by one in the d) positron emission and the e) electron capture radioactive decay. These radioactive decays are two of three common forms of the Beta Decay which occurred when the proton released a positron and a neutron emitted an electron. The Beta Decay can increase or decrease the atomic number.