Final answer:
Kenneth and Mamie Clark's research on doll preference among African American children contributed to the Supreme Court decision to end segregated schools.
Step-by-step explanation:
Kenneth and Mamie Clark's research on doll preference among African American children played a pivotal role in the U.S. Supreme Court decision to outlaw segregated schools in 1954. The Clarks conducted experiments where Black children were asked to choose between dolls with different skin colors, hair types, and features. The majority of Black children chose the white doll, illustrating the negative effects of segregation on their self-esteem and sense of identity. This research provided evidence that segregation was inherently discriminatory and violated the Fourteenth Amendment of the Constitution.