Answer:
B. Robert Millikan
Explanation:
J.J. Thompson gave the plum pudding model of the atom.
Millikan determined the charge and mass of an electron. Millikan’s oil drop experiment was conducted to measure the elementary charge ( or a unit charge).
Eugen Goldstein discovered the anode rays or protons.
Rutherford conducted the gold foil experiment and proved that the center of the nucleus has a positive charge and most of the atom’s mass lies in a small volume.
