Answer:
d.
Step-by-step explanation:
a. beta radiation - electrons that have negative charge, and when they leave a nucleus , the charge or atomic number of the nucleus will change.
b. Alpha radiation - nuclei of He, atomic number and mass number will be changed.
c. positron radiation - positrons are similar to electrons but have positive charge, so , the charge or atomic number of the nucleus will change.
d. gamma radiation is electromagnetic waves, does not have charge and mass.