which scientist is known for developing the planetary model of the atom?\no niels bohr\no albert einstein\no…

Brief Explanations:

Niels Bohr developed the planetary model of the atom, where electrons orbit the nucleus similar to planets orbiting the sun. Einstein is known for theories of relativity, Rydberg for the Rydberg formula related to atomic spectra, and Millikan for the oil - drop experiment to measure the electron's charge.

Answer:

A. Niels Bohr