Which court ruling created the separate but equal doctrine, which upheld state laws that mandated racial separation in schools and all public accommodations?

The Plessy v. Fergisun is the court ruling which led to the creation of the separate but uniform doctrine, wherein it approved state laws that required racial separation in public accommodations and schools.

The Plessy v. Fergisun court ruling was issued in 1896 and it was the landmark decision of the United States Supreme Court. It is the doctrine that is now known as “separate but equal”.

seeing as no choices were provided, i'll do my best to answer it from knowledge.

job specialization promotes work ethic to the person doing the job. he/she may be strong in the arms and able to lift things, specializing him/her in a job where you lift and carry.