C. The NAACP was formed in response to the worsening of social conditions for African Americans following the court’s decision.
This option best reflects the historical context of Plessy v. Ferguson (1896), which upheld the doctrine of "separate but equal" and led to the institutionalization of racial segregation, resulting in deteriorating conditions for African Americans. The NAACP, founded in 1909, aimed to combat these injustices and promote civil rights.