Final answer:
The correct statement about the Bohr model is that electrons move in stable orbits around the nucleus and emit radiation only when jumping between these orbits, which are quantized to specific energies.
Step-by-step explanation:
The Bohr model was the first successful model of the hydrogen atom and is known for its postulates that redefined atomic structure. The correct statement about the Bohr model is as follows: Electrons move in stable, circular orbits around the nucleus without radiating energy unless they jump between orbits with the emission or absorption of a photon. These orbits, or energy levels, are not continuous but quantized; meaning, electrons can only exist in specific orbits with fixed energies.
In other words, according to the Bohr model, electrons do not emit radiation as they move in stable orbits, contrary to what one might expect based on classical physics. And contrary to proposition d), electrons cannot exist in any orbit; their energy levels are quantized, meaning that the electrons can only exist in certain allowed orbits or energy levels. This model also addressed the limitations of the Rutherford model and the emission spectrum of hydrogen.