Final answer:
The main effect of the Jim Crow system was legalized segregation and discrimination against African Americans in the United States.
Step-by-step explanation:
The main effect of the Jim Crow system was the legalized segregation and discrimination against African Americans in the United States from the late 19th century to the mid-20th century. This system enforced racial segregation in public facilities, education, housing, employment, and voting rights, perpetuating racial inequality and denying African Americans their civil rights and opportunities. For example, African Americans were subjected to separate schools, bathrooms, and seating areas in public transportation.
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