How did the study of the atom contribute to the development of the modern periodic table?

A. Moseley used atomic numbers to organize elements into groups and periods.
B. Mendeleev used atomic numbers to organize elements into groups and periods.
C. Rutherford's discovery of the proton also lead to the discovery of the electron.
D. Thompson used the charge of the electron to determine its mass.

A. Moseley used atomic numbers to organize elements into groups and periods.