When a positively charged alpha particle is passed through a thin gold foil, most of the particles pass straight through without deflection. Based on…

1. AThe positive charge and mass are concentrated at the centre of the atom.
2. BThe atom contains a small, dense nucleus that repels alpha particles.
3. CThe positive charge is uniformly distributed throughout the atom, and electrons are embedded in it.
4. DElectrons revolve around the nucleus in fixed orbits.