Proton was discovered by:
Goldstein
Explanation for the correct option:
Option B: Goldstein:
Thus, proton was discovered by Goldstein
Explanation for incorrect options:
Option A: Rutherford:
Rutherford gave model of the atom by performing an experiment with thin gold foil and positively charged alpha particles.
Option C: Chadwick:
Chadwick bombarded a thin sheet of Beryllium (Be) by alpha particles, electrically neutral particles having a mass slightly greater than that of protons i.e. neutrons were emitted. He discovered neutrons.
Option D: J.J Thompson:
J.J Thompson discovered electrons by performing experiments on electrical conduction of gases through partially evacuated tubes, known as cathode ray discharge tube. He discovered electrons.
Thus, Option (B) is the correct option.