What caused the great migration of the early 1900

The desire of Black Southerners to escape segregation.

Explanation:

The Great Migration of the early 1900s was a movement of large numbers of people from the South to the North of the United States. This movement followed the Civil War and Reconstruction period, and was largely a consequence of the negative experiences of Black people in the South. As segregation and discrminatory policies became more common, many people believed that they were going to find better opportunities in the North.

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.