Which one of the following scientists mentioned that an electron in an atom could revolve in certain stable orbits without the emission of radiant energy?

Niels Bohr proposed his atomic model in 1913, postulating that electrons revolve around the nucleus only in certain discrete, stable orbits (called stationary orbits) without radiating energy. Energy is emitted or absorbed only when an electron jumps from one orbit to another. Rutherford's model could not explain the stability of atoms, J.J. Thomson proposed the plum-pudding model, and Einstein contributed to quantum theory through the photoelectric effect but did not propose stable electron orbits. Therefore, Niels Bohr is the correct answer.