The best option that analyzes the ruling of Plessy v. Ferguson in terms of individual freedoms and equal protections is:
Plessy v. Ferguson established the separate but equal doctrine that segregated Black Americans in public spaces.
This statement captures the essence of the ruling, which upheld the constitutionality of racial segregation under the "separate but equal" doctrine, fundamentally impacting civil rights and individual freedoms for Black Americans in various public spaces, not just limited to public transportation.