In 1887, prior to the introduction of the length-contraction fudge factor, the Michelson-Morley experiment was compatible with

(A) speed of light independent of the speed of the emitter?

(B) speed of light dependent on the speed of the emitter?

(C) speed of light both independent of and dependent on the speed of the emitter?

Clues:

"The null result of the Michelson-Morley experiment was unhelpful and possibly counter-productive in Einstein's investigations of an emission theory of light, for the null result is predicted by an emission theory." http://philsci-archive.pitt.edu/12289/1/Einstein_Discover.pdf

"Emission theory, also called emitter theory or ballistic theory of light, was a competing theory for the special theory of relativity, explaining the results of the Michelson–Morley experiment of 1887...The name most often associated with emission theory is Isaac Newton. In his corpuscular theory Newton visualized light "corpuscles" being thrown off from hot bodies at a nominal speed of c with respect to the emitting object, and obeying the usual laws of Newtonian mechanics, and we then expect light to be moving towards us with a speed that is offset by the speed of the distant emitter (c ± v)." https://en.wikipedia.org/wiki/Emission_theory

"Moreover, if light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether." Banesh Hoffmann, Relativity and Its Roots, p.92 https://www.amazon.com/Relativity-Its-Roots-Banesh-Hoffmann/dp/0486406768

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Pentcho Valev

In 1887, prior to the introduction of the length-contraction fudge factor by FitzGerald and Lorentz, the Michelson-Morley experiment was compatible with

(A) speed of light independent of the speed of the light source?

(B) speed of light dependent on the speed of the light source?

(C) speed of light both independent of and dependent on the speed of the light source?

Clearly, (A) and (B) cannot be both true. (C) is an idiocy of course - I added it because some Einsteinians do give similar answers. Final conclusion: (A) is wrong, (B) is correct.

Banesh Hoffmann explains the situation quite well. Without recourse to fudge factors ("contracting lengths, local time, or Lorentz transformations"), the Michelson-Morley experiment is only compatible with Newton's variable speed of light:

"If light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether." Banesh Hoffmann, Relativity and Its Roots, p.92 https://www.amazon.com/Relativity-Its-Roots-Banesh-Hoffmann/dp/0486406768

https://qph.cf2.quoracdn.net/main-qimg-f10f1c25528a4e5edc9bae200640f31c-pjlq

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Pentcho Valev

Neither. Postulating something or not is a matter of choice.
Experiments can't determine it.